diff --git a/.env.example b/.env.example
index bfcff31..d5f5b5e 100644
--- a/.env.example
+++ b/.env.example
@@ -34,3 +34,10 @@ ONLYOFFICE_PROJECT_ID=33
 # MINIO_BUCKET=office
 # MINIO_ACCESS_KEY=
 # MINIO_SECRET_KEY=
+
+# oo search — direct Elasticsearch access for name + content search. ES lives
+# inside the OnlyOffice VM on localhost:9200; expose it with an SSH tunnel
+# (see docs/elasticsearch.md). ONLYOFFICE_ES_INDEX defaults to files_file.
+# ONLYOFFICE_ES_URL=http://127.0.0.1:9200
+# ONLYOFFICE_ES_INDEX=files_file
+# ONLYOFFICE_TENANT=
diff --git a/README.md b/README.md
index 50870c4..1458a5f 100644
--- a/README.md
+++ b/README.md
@@ -678,6 +678,25 @@ oo dav download 22881 --to ./copy.pdf # default path: ./<server title>
 oo dav fileops                        # active move/copy operations (status polling)
 ```
 
+### Search (`oo search`)
+
+Full-text search over the Documents index. The REST endpoint
+`/api/2.0/files/@search/{query}` only searches file names in the database, so
+`oo search` talks to the OnlyOffice **Elasticsearch** directly (index
+`files_file`). Name search is default; `--content` also matches extracted
+document text (`document.attachment.content`, Office formats only).
+See [`docs/elasticsearch.md`](docs/elasticsearch.md) for the tunnel setup.
+
+```bash
+oo search "Rechnung"                          # names only
+oo search "Mahngebühr" --content              # names + document text
+oo search "Rechnung" --folder 649 --limit 50
+oo search "Rechnung" --json                   # shorthand for -o json
+```
+
+Requires `ONLYOFFICE_ES_URL` (plus optional `ONLYOFFICE_ES_INDEX`,
+`ONLYOFFICE_TENANT`).
+
 ### Bulk tools (`cmd/`)
 
 Small single-purpose binaries for bulk Documents work. All of them pace
@@ -714,6 +733,7 @@ kontolink IN.xlsx oo-index.tsv OUT.xlsx [FILE_ID] [AMOUNTS_TSV]
 | `docs` | `tools`, `convert`, `optimize`, `ocr`, `hocr`, `as-md`, `put-md`, `put-txt`, `put-xlsx` |
 | `catalog` | `match`, `merge`, `apply`, `scan-contacts`, `scan-projects`, `scan-thunderbird` |
 | `dav` | `ls`, `move`, `copy`, `mkdir`, `rename-file`, `rename-folder`, `download`, `fileops` |
+| `search` | `QUERY` (`--content`, `--folder ID`, `--limit N`, `--json`) |
 
 The CLI reads only `.env` from the current working directory (godotenv is a
 CLI-only concern — the library itself never loads dotfiles).
diff --git a/cmd/oo/main.go b/cmd/oo/main.go
index c91baaa..82ab8e8 100644
--- a/cmd/oo/main.go
+++ b/cmd/oo/main.go
@@ -18,6 +18,7 @@
 //	oo docs          tools | convert | optimize | ocr | hocr | as-md | put-md | put-txt | put-xlsx
 //	oo catalog       match | merge | apply | scan-contacts | scan-projects | scan-thunderbird
 //	oo dav           ls | move | copy | mkdir | rename-file | rename-folder | download | fileops
+//	oo search        QUERY [--content] [--folder ID] [--limit N] [--json]
 //
 // CRM association rules: docs/crm-associations.md
 //
diff --git a/cmd/oo/search.go b/cmd/oo/search.go
new file mode 100644
index 0000000..2ceab0e
--- /dev/null
+++ b/cmd/oo/search.go
@@ -0,0 +1,72 @@
+package main
+
+import (
+	onlyoffice "github.com/eslider/go-onlyoffice"
+	"github.com/spf13/cobra"
+)
+
+func init() {
+	rootCmd.AddCommand(searchCmd())
+}
+
+// searchCmd queries the OnlyOffice Elasticsearch index directly. The REST
+// /api/2.0/files/@search endpoint only searches file names in the database;
+// content search needs ES (see docs/elasticsearch.md).
+func searchCmd() *cobra.Command {
+	var (
+		content bool
+		folder  string
+		limit   int
+		asJSON  bool
+	)
+	cmd := &cobra.Command{
+		Use:   "search QUERY",
+		Short: "Full-text search over documents by name, optionally by content (Elasticsearch)",
+		Long: "Search the OnlyOffice Documents index.\n\n" +
+			"By default only file names are matched. With --content the query also\n" +
+			"matches extracted document text (document.attachment.content); this covers\n" +
+			"Office formats (docx/xlsx/pptx) and is slower.\n\n" +
+			"Requires ONLYOFFICE_ES_URL (and optionally ONLYOFFICE_ES_INDEX,\n" +
+			"ONLYOFFICE_TENANT). See docs/elasticsearch.md for the tunnel setup.",
+		Args: cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if asJSON {
+				outputFormat = "json"
+			}
+			es, err := onlyoffice.NewESSearcher(onlyoffice.ESConfigFromEnv())
+			if err != nil {
+				return err
+			}
+			hits, err := es.Search(cmd.Context(), onlyoffice.SearchQuery{
+				Text:      args[0],
+				InContent: content,
+				FolderID:  folder,
+				Limit:     limit,
+			})
+			if err != nil {
+				return err
+			}
+			rows := make([]map[string]any, 0, len(hits))
+			for _, h := range hits {
+				rows = append(rows, map[string]any{
+					"id":        h.ID,
+					"title":     h.Title,
+					"folder":    h.ParentID,
+					"score":     h.Score,
+					"highlight": h.Highlight,
+				})
+			}
+			if outputFormat == "json" {
+				printJSON(rows)
+				return nil
+			}
+			printTable([]string{"id", "title", "folder", "score", "highlight"}, rows)
+			return nil
+		},
+	}
+	cmd.Flags().BoolVar(&content, "content", false, "also match extracted document content")
+	cmd.Flags().StringVar(&folder, "folder", "", "limit to a Documents folder id")
+	cmd.Flags().IntVar(&limit, "limit", 20, "maximum number of results")
+	cmd.Flags().BoolVar(&asJSON, "json", false, "shorthand for --output json")
+	return cmd
+}
diff --git a/cmd/oo/search_test.go b/cmd/oo/search_test.go
new file mode 100644
index 0000000..ea1716c
--- /dev/null
+++ b/cmd/oo/search_test.go
@@ -0,0 +1,46 @@
+package main
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+)
+
+func TestSearchCommandRegisteredWithFlags(t *testing.T) {
+	cmd, _, err := rootCmd.Find([]string{"search"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cmd.Name() != "search" {
+		t.Fatalf("search resolved to %q", cmd.Name())
+	}
+	for _, name := range []string{"content", "folder", "limit", "json"} {
+		if cmd.Flags().Lookup(name) == nil {
+			t.Errorf("search: missing --%s flag", name)
+		}
+	}
+	if got := cmd.Flags().Lookup("limit").DefValue; got != "20" {
+		t.Errorf("--limit default = %q, want 20", got)
+	}
+}
+
+func TestSearchWithoutESURLIsClearError(t *testing.T) {
+	clearEnv(t, "ONLYOFFICE_ES_URL", "ONLYOFFICE_ES_INDEX", "ONLYOFFICE_TENANT")
+	errBuf := &bytes.Buffer{}
+	rootCmd.SetErr(errBuf)
+	rootCmd.SetOut(&bytes.Buffer{})
+	rootCmd.SetArgs([]string{"search", "Rechnung"})
+	t.Cleanup(func() {
+		rootCmd.SetArgs(nil)
+		rootCmd.SetOut(nil)
+		rootCmd.SetErr(nil)
+	})
+
+	err := rootCmd.Execute()
+	if err == nil {
+		t.Fatal("expected error without ONLYOFFICE_ES_URL")
+	}
+	if !strings.Contains(err.Error(), "ONLYOFFICE_ES_URL") {
+		t.Fatalf("error %q missing ONLYOFFICE_ES_URL", err.Error())
+	}
+}
diff --git a/docs/elasticsearch.md b/docs/elasticsearch.md
new file mode 100644
index 0000000..05df5d6
--- /dev/null
+++ b/docs/elasticsearch.md
@@ -0,0 +1,125 @@
+---
+type: reference
+status: current
+related:
+  - README.md
+  - file_es.go
+---
+
+# Elasticsearch — полнотекстовый поиск OnlyOffice
+
+## Что это
+
+Полнотекстовый поиск OnlyOffice Workspace работает на **Elasticsearch**.
+Клиент на сервере — NEST. Индекс — имя таблицы.
+
+Для файлов индекс `files_file`:
+
+| поле | тип | смысл |
+|------|-----|-------|
+| `id` | integer | id файла (тот же, что в REST/Documents) |
+| `title` | text (`whitespacecustom`) | имя файла |
+| `tenantId` | integer | тенант (портал) |
+| `folders` | nested | список папок: `folderId` (строка), `id`, `tenantId` |
+| `document.attachment.content` | text (`document`) | извлеченный текст (ingest-attachment) |
+| `document.attachment.content_type` | text | MIME |
+
+Важно:
+- Живой сервер — **Elasticsearch 7.16.3**, кластер `elasticsearch`.
+- REST `GET /api/2.0/files/@search/{query}` ищет **только по имени в БД**
+  (`fileDao.Search`), ES не задействует. Для поиска по содержимому нужен
+  прямой ES — это и делает `oo search`.
+- `title` analyzer `whitespacecustom` режет по пробелам и lower-case. Полное
+  имя файла — один токен (`Rechnung-4711.pdf`), поэтому поиск по имени ищет
+  слово целиком, а не подстроку.
+- `document.attachment.content` заполняется **только для Office-форматов**
+  (docx / xlsx / pptx). У PDF/txt, залитых через API, контент не извлекается.
+- Индексация асинхронная (TeamLabSvc) — файл появляется в ES не мгновенно.
+
+## Доступ
+
+ES слушает `127.0.0.1:9200` **внутри** VM OnlyOffice. Снаружи порт закрыт,
+SSH в VM открыт на хосте как `127.0.0.1:32` (контейнер `onlyoffice-v2`,
+QEMU). Схема — SSH-туннель.
+
+```bash
+# из корня go-onlyoffice (ключ и хост — как в infra-доках)
+ssh -f -N -o ControlMaster=no -o ControlPath=none \
+    -p 32 -i ~/.ssh/id_ed25519 \
+    -L 9200:127.0.0.1:9200 root@127.0.0.1
+
+curl -s http://127.0.0.1:9200/ | head            # tagline + version
+curl -s 'http://127.0.0.1:9200/_cat/indices?h=index,docs.count'
+```
+
+`-o ControlMaster=no -o ControlPath=none` обязательны: иначе forward уходит
+в persistent master-соединение из `~/.ssh/config` и порт остаётся занят.
+
+Проверить, что туннель жив:
+
+```bash
+curl -s http://127.0.0.1:9200/files_file/_count
+```
+
+## Переменные
+
+| env | default | смысл |
+|-----|---------|-------|
+| `ONLYOFFICE_ES_URL` | — (обязателен) | `scheme://host:port` ES |
+| `ONLYOFFICE_ES_INDEX` | `files_file` | индекс |
+| `ONLYOFFICE_TENANT` | пусто (все) | фильтр `tenantId` |
+
+Имена — в [`.env.example`](../.env.example). Секретов нет: ES без пароля.
+
+## CLI
+
+```bash
+ONLYOFFICE_ES_URL=http://127.0.0.1:9200 oo search "Rechnung"
+ONLYOFFICE_ES_URL=http://127.0.0.1:9200 oo search "Mahngebühr" --content
+oo search "Rechnung" --folder 649 --limit 50 --json
+```
+
+Флаги: `--content` (искать и по тексту), `--folder ID` (папка
+`folders.folderId`), `--limit N` (по умолчанию 20, максимум 200),
+`--json` = `-o json`.
+
+## Библиотека
+
+`file_es.go` — `ESSearcher` (`Name() = "elasticsearch"`), прямой ES REST на
+stdlib `net/http`:
+
+```go
+es, _ := onlyoffice.NewESSearcher(onlyoffice.ESConfigFromEnv())
+hits, _ := es.Search(ctx, onlyoffice.SearchQuery{
+    Text: "Rechnung", InContent: true, Limit: 20,
+})
+```
+
+Запрос: `multi_match` по `title^2` (+ `document.attachment.content` при
+`InContent`), фильтры `tenantId` и `folders.folderId`, `_source`
+id/title/folders, `highlight` для фрагмента. Ответ → `[]SearchHit` (модель из
+эпика #34; пока объявлена в `file_es.go`, переедет в `file_core.go` с F1 #35).
+
+## Тесты
+
+```bash
+# unit — чистые builders/парсеры, без сети
+go test ./ -run ES
+
+# integration — нужен ONLYOFFICE_ES_URL (+ креды REST для залива)
+set -a; . .env; set +a
+ONLYOFFICE_ES_URL=http://127.0.0.1:9200 ONLYOFFICE_TENANT=1 \
+  go test -tags=integration -run TestIntegrationESSearch -v .
+```
+
+Интеграционный тест заливает временный xlsx (в имени и в ячейке — уникальные
+токены), ждёт индексации, проверяет поиск по имени и по содержимому, затем
+удаляет проект.
+
+## Грабли
+
+- `locale`/версия ES: 7.16.3, `_search` совместим с REST 7.x.
+- ES без auth и слушает только localhost — туннель обязателен.
+- Фильтр `tenantId` сузит выдачу; без него видны документы всех тенантов.
+- Поиск по содержимому PDF, залитых через API, не работает (нет
+  `attachment.content`) — только Office-форматы.
diff --git a/file_es.go b/file_es.go
new file mode 100644
index 0000000..9c2db76
--- /dev/null
+++ b/file_es.go
@@ -0,0 +1,285 @@
+package onlyoffice
+
+// Elasticsearch backend of the unified file client (epic #34, F3 #37).
+//
+// OnlyOffice full-text search runs on Elasticsearch (index `files_file`, NEST
+// client on the server). The REST endpoint GET /api/2.0/files/@search/{query}
+// only searches file names in the database, so content search needs a direct
+// ES query. The live server is Elasticsearch 7.16.3; the request shape below
+// is plain REST and stays stdlib-only, matching the repo's no-extra-deps rule.
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// The canonical model (Kind, Entry, SearchQuery, SearchHit, Searcher) lives in
+// file_core.go (F1 #35).
+
+const (
+	defaultESIndex    = "files_file"
+	defaultESLimit    = 20
+	maxESLimit        = 200
+	maxESResponseSize = 8 << 20
+)
+
+// ESConfig configures the direct Elasticsearch searcher.
+type ESConfig struct {
+	URL    string // scheme://host:port of the ES HTTP endpoint
+	Index  string // index name, default files_file
+	Tenant string // tenantId filter, empty means all tenants
+}
+
+// ESConfigFromEnv reads ONLYOFFICE_ES_URL, ONLYOFFICE_ES_INDEX (default
+// files_file) and ONLYOFFICE_TENANT. The library never loads dotfiles — the
+// CLI does that.
+func ESConfigFromEnv() ESConfig {
+	return ESConfig{
+		URL:    strings.TrimRight(strings.TrimSpace(os.Getenv("ONLYOFFICE_ES_URL")), "/"),
+		Index:  firstNonEmpty(os.Getenv("ONLYOFFICE_ES_INDEX"), defaultESIndex),
+		Tenant: strings.TrimSpace(os.Getenv("ONLYOFFICE_TENANT")),
+	}
+}
+
+// ESSearcher queries OnlyOffice's Elasticsearch index directly for file name
+// and document content.
+type ESSearcher struct {
+	cfg  ESConfig
+	http *http.Client
+}
+
+// NewESSearcher returns a searcher for the OnlyOffice Elasticsearch index.
+// The URL is required; an empty index falls back to files_file.
+func NewESSearcher(cfg ESConfig) (*ESSearcher, error) {
+	if strings.TrimSpace(cfg.URL) == "" {
+		return nil, fmt.Errorf("onlyoffice: elasticsearch URL is empty (set ONLYOFFICE_ES_URL)")
+	}
+	cfg.URL = strings.TrimRight(cfg.URL, "/")
+	if cfg.Index == "" {
+		cfg.Index = defaultESIndex
+	}
+	return &ESSearcher{cfg: cfg, http: &http.Client{Timeout: 30 * time.Second}}, nil
+}
+
+// Name implements Searcher.
+func (s *ESSearcher) Name() string { return "elasticsearch" }
+
+// Search runs a multi_match over title (and, when q.InContent is set,
+// document.attachment.content), filtered by tenant and optional folder.
+func (s *ESSearcher) Search(ctx context.Context, q SearchQuery) ([]SearchHit, error) {
+	q.Text = strings.TrimSpace(q.Text)
+	if q.Text == "" {
+		return nil, fmt.Errorf("onlyoffice: empty search query")
+	}
+	body, err := json.Marshal(esSearchRequest(q, s.cfg.Tenant))
+	if err != nil {
+		return nil, fmt.Errorf("onlyoffice: build elasticsearch query: %w", err)
+	}
+	endpoint := s.cfg.URL + "/" + s.cfg.Index + "/_search"
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, bytes.NewReader(body))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Accept", "application/json")
+	resp, err := s.http.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("onlyoffice: elasticsearch search: %w", err)
+	}
+	defer resp.Body.Close()
+	raw, err := io.ReadAll(io.LimitReader(resp.Body, maxESResponseSize))
+	if err != nil {
+		return nil, err
+	}
+	if resp.StatusCode >= 400 {
+		return nil, fmt.Errorf("onlyoffice: elasticsearch search: %d %s", resp.StatusCode, truncate(string(raw), 400))
+	}
+	return parseESSearchResponse(raw)
+}
+
+// esSearchRequest builds the ES query body. Pure, so it is unit-tested.
+func esSearchRequest(q SearchQuery, tenant string) esRequest {
+	limit := q.Limit
+	if limit <= 0 {
+		limit = defaultESLimit
+	}
+	if limit > maxESLimit {
+		limit = maxESLimit
+	}
+	fields := []string{"title^2"}
+	if q.InContent {
+		fields = append(fields, "document.attachment.content")
+	}
+	must := []esClause{{MultiMatch: &esMultiMatch{Query: q.Text, Fields: fields}}}
+
+	var filter []esClause
+	if t := strings.TrimSpace(tenant); t != "" {
+		filter = append(filter, esClause{Term: map[string]any{"tenantId": numericOrString(t)}})
+	}
+	if f := strings.TrimSpace(q.FolderID); f != "" {
+		filter = append(filter, esClause{Term: map[string]any{"folders.folderId": f}})
+	}
+	for _, ext := range normalizeExtensions(q.Extensions) {
+		filter = append(filter, esClause{Wildcard: map[string]any{"title": "*." + ext}})
+	}
+
+	highlightFields := map[string]struct{}{"title": {}}
+	if q.InContent {
+		highlightFields["document.attachment.content"] = struct{}{}
+	}
+	return esRequest{
+		Size:      limit,
+		Source:    []string{"id", "title", "folders"},
+		Query:     esQuery{Bool: esBool{Must: must, Filter: filter}},
+		Highlight: esHighlight{PreTags: []string{"<em>"}, PostTags: []string{"</em>"}, Fields: highlightFields},
+	}
+}
+
+// normalizeExtensions lowercases, trims leading dots and drops empties.
+func normalizeExtensions(exts []string) []string {
+	out := make([]string, 0, len(exts))
+	seen := map[string]bool{}
+	for _, e := range exts {
+		e = strings.ToLower(strings.TrimSpace(strings.TrimPrefix(strings.TrimSpace(e), ".")))
+		if e == "" || seen[e] {
+			continue
+		}
+		seen[e] = true
+		out = append(out, e)
+	}
+	return out
+}
+
+// numericOrString keeps an integer-looking filter value numeric (tenantId is
+// a long) and leaves anything else as a string (folderId is a text token).
+func numericOrString(s string) any {
+	if n, err := strconv.ParseInt(s, 10, 64); err == nil {
+		return n
+	}
+	return s
+}
+
+// esRequest is the subset of the ES query DSL this client emits.
+type esRequest struct {
+	Size      int         `json:"size"`
+	Source    []string    `json:"_source"`
+	Query     esQuery     `json:"query"`
+	Highlight esHighlight `json:"highlight"`
+}
+
+type esQuery struct {
+	Bool esBool `json:"bool"`
+}
+
+type esBool struct {
+	Must   []esClause `json:"must,omitempty"`
+	Filter []esClause `json:"filter,omitempty"`
+}
+
+type esClause struct {
+	MultiMatch *esMultiMatch  `json:"multi_match,omitempty"`
+	Term       map[string]any `json:"term,omitempty"`
+	Wildcard   map[string]any `json:"wildcard,omitempty"`
+}
+
+type esMultiMatch struct {
+	Query  string   `json:"query"`
+	Fields []string `json:"fields"`
+}
+
+type esHighlight struct {
+	PreTags  []string            `json:"pre_tags,omitempty"`
+	PostTags []string            `json:"post_tags,omitempty"`
+	Fields   map[string]struct{} `json:"fields"`
+}
+
+// esResponse is the subset of an ES search response we consume.
+type esResponse struct {
+	Took int `json:"took"`
+	Hits struct {
+		Total struct {
+			Value    int    `json:"value"`
+			Relation string `json:"relation"`
+		} `json:"total"`
+		Hits []esResponseHit `json:"hits"`
+	} `json:"hits"`
+}
+
+type esResponseHit struct {
+	ID     string  `json:"_id"`
+	Score  float64 `json:"_score"`
+	Source struct {
+		ID      int    `json:"id"`
+		Title   string `json:"title"`
+		Folders []struct {
+			FolderID string `json:"folderId"`
+			ID       int    `json:"id"`
+		} `json:"folders"`
+	} `json:"_source"`
+	Highlight map[string][]string `json:"highlight"`
+}
+
+// parseESSearchResponse converts an ES search response into SearchHit values.
+// Pure, so it is unit-tested.
+func parseESSearchResponse(raw []byte) ([]SearchHit, error) {
+	var r esResponse
+	if err := json.Unmarshal(raw, &r); err != nil {
+		return nil, fmt.Errorf("onlyoffice: decode elasticsearch response: %w", err)
+	}
+	hits := make([]SearchHit, 0, len(r.Hits.Hits))
+	for _, h := range r.Hits.Hits {
+		id := strconv.Itoa(h.Source.ID)
+		if h.Source.ID == 0 {
+			id = h.ID
+		}
+		var parent string
+		path := make([]string, 0, len(h.Source.Folders))
+		for i, f := range h.Source.Folders {
+			path = append(path, f.FolderID)
+			if i == 0 {
+				parent = f.FolderID
+			}
+		}
+		hits = append(hits, SearchHit{
+			Entry: Entry{
+				ID:       id,
+				ParentID: parent,
+				Title:    h.Source.Title,
+				Kind:     File,
+				Provider: "elasticsearch",
+			},
+			Score:     h.Score,
+			Highlight: esHighlightText(h.Highlight),
+			Path:      path,
+		})
+	}
+	return hits, nil
+}
+
+var esHighlightTag = regexp.MustCompile(`</?em[^>]*>`)
+
+// esHighlightText flattens a highlight map into one plain-text snippet,
+// preferring the content fragment over the title.
+func esHighlightText(hl map[string][]string) string {
+	for _, key := range []string{"document.attachment.content", "title"} {
+		frags := hl[key]
+		if len(frags) == 0 {
+			continue
+		}
+		clean := make([]string, 0, len(frags))
+		for _, f := range frags {
+			clean = append(clean, esHighlightTag.ReplaceAllString(f, ""))
+		}
+		return strings.Join(clean, " … ")
+	}
+	return ""
+}
diff --git a/file_es_integration_test.go b/file_es_integration_test.go
new file mode 100644
index 0000000..ce4e891
--- /dev/null
+++ b/file_es_integration_test.go
@@ -0,0 +1,135 @@
+//go:build integration
+
+package onlyoffice
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/xuri/excelize/v2"
+)
+
+// TestIntegrationESSearch uploads a throwaway workbook and verifies that the
+// direct Elasticsearch search finds it by file name and by content.
+//
+// The content index (document.attachment.content) is only populated for Office
+// formats (docx/xlsx/pptx), so the fixture is an xlsx whose cell carries a
+// unique token. Requires ONLYOFFICE_ES_URL (a reachable ES endpoint — in the
+// current setup a tunnel to the ES inside the OnlyOffice VM, see
+// docs/elasticsearch.md) plus the regular REST credentials for the upload.
+// Skips when either is missing.
+func TestIntegrationESSearch(t *testing.T) {
+	esURL := strings.TrimSpace(os.Getenv("ONLYOFFICE_ES_URL"))
+	if esURL == "" {
+		t.Skip("ONLYOFFICE_ES_URL not set — skipping Elasticsearch integration test")
+	}
+	c := liveClient(t)
+	t.Cleanup(func() { cleanupTestProjects(t, c) })
+
+	stamp := time.Now().UTC().Format("20060102-150405")
+	nameToken := "goesname" + stamp
+	contentToken := "goescontent" + stamp
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
+	defer cancel()
+
+	project, err := c.CreateProject(NewProjectRequest{
+		Title:       testProjectPrefix + "es-" + stamp,
+		Description: "go-onlyoffice elasticsearch integration",
+	})
+	if err != nil {
+		t.Fatalf("CreateProject: %v", err)
+	}
+	if project.ID == nil {
+		t.Fatal("created project without id")
+	}
+	pid := strconv.Itoa(*project.ID)
+
+	title := nameToken + ".xlsx"
+	localPath := filepath.Join(t.TempDir(), title)
+	book := excelize.NewFile()
+	if err := book.SetCellValue("Sheet1", "A1", "OnlyOffice Elasticsearch content fixture "+contentToken); err != nil {
+		t.Fatalf("SetCellValue: %v", err)
+	}
+	if err := book.SaveAs(localPath); err != nil {
+		t.Fatalf("SaveAs: %v", err)
+	}
+
+	entry, err := c.UploadProjectFile(ctx, pid, localPath)
+	if err != nil {
+		t.Fatalf("UploadProjectFile: %v", err)
+	}
+	fileID := strconv.Itoa(int(FileEntryNumericID(entry)))
+	if fileID == "0" {
+		t.Fatalf("upload returned no file id: %+v", entry)
+	}
+
+	es, err := NewESSearcher(ESConfig{
+		URL:    esURL,
+		Index:  os.Getenv("ONLYOFFICE_ES_INDEX"),
+		Tenant: os.Getenv("ONLYOFFICE_TENANT"),
+	})
+	if err != nil {
+		t.Fatalf("NewESSearcher: %v", err)
+	}
+
+	// Indexing is asynchronous on the server; poll until the file shows up.
+	// The server's title analyzer splits on whitespace, so the name query is
+	// the full file name token (including extension), as a user would type it.
+	nameHit := waitForHit(t, ctx, es, SearchQuery{Text: title}, fileID)
+	if nameHit.Title != title {
+		t.Errorf("name hit title = %q, want %q", nameHit.Title, title)
+	}
+	contentHit := waitForHit(t, ctx, es, SearchQuery{Text: contentToken, InContent: true}, fileID)
+	if contentHit.Highlight == "" {
+		t.Error("content hit has no highlight fragment")
+	}
+	if !strings.Contains(contentHit.Title, nameToken) {
+		t.Errorf("content hit title = %q, want the uploaded workbook", contentHit.Title)
+	}
+
+	// The content token is absent from the title, so a name-only search must
+	// not return the file — this proves the content field is really queried.
+	if hits := searchQuiet(t, es, SearchQuery{Text: contentToken}); len(hits) != 0 {
+		t.Errorf("name-only search for content token returned %d hits, want 0", len(hits))
+	}
+}
+
+// waitForHit polls ES until the file with fileID appears and returns that hit.
+func waitForHit(t *testing.T, ctx context.Context, s *ESSearcher, q SearchQuery, fileID string) SearchHit {
+	t.Helper()
+	var lastErr error
+	for {
+		hits, err := s.Search(ctx, q)
+		if err != nil {
+			lastErr = err
+		} else {
+			for _, h := range hits {
+				if h.ID == fileID {
+					return h
+				}
+			}
+		}
+		select {
+		case <-ctx.Done():
+			t.Fatalf("search %q: file %s not indexed in time (last err: %v)", q.Text, fileID, lastErr)
+		case <-time.After(3 * time.Second):
+		}
+	}
+}
+
+func searchQuiet(t *testing.T, s *ESSearcher, q SearchQuery) []SearchHit {
+	t.Helper()
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	hits, err := s.Search(ctx, q)
+	if err != nil {
+		t.Fatalf("Search(%q): %v", q.Text, err)
+	}
+	return hits
+}
diff --git a/file_es_test.go b/file_es_test.go
new file mode 100644
index 0000000..ee60ef1
--- /dev/null
+++ b/file_es_test.go
@@ -0,0 +1,188 @@
+package onlyoffice
+
+import (
+	"encoding/json"
+	"reflect"
+	"testing"
+)
+
+func TestESSearchRequestNameOnly(t *testing.T) {
+	got := esSearchRequest(SearchQuery{Text: "Rechnung"}, "1")
+	if got.Size != defaultESLimit {
+		t.Errorf("size = %d, want %d", got.Size, defaultESLimit)
+	}
+	if !reflect.DeepEqual(got.Source, []string{"id", "title", "folders"}) {
+		t.Errorf("_source = %v", got.Source)
+	}
+	if len(got.Query.Bool.Must) != 1 || got.Query.Bool.Must[0].MultiMatch == nil {
+		t.Fatalf("must = %+v, want one multi_match", got.Query.Bool.Must)
+	}
+	mm := got.Query.Bool.Must[0].MultiMatch
+	if mm.Query != "Rechnung" {
+		t.Errorf("query = %q", mm.Query)
+	}
+	if !reflect.DeepEqual(mm.Fields, []string{"title^2"}) {
+		t.Errorf("fields = %v, want title only", mm.Fields)
+	}
+	if _, ok := got.Highlight.Fields["document.attachment.content"]; ok {
+		t.Error("content highlight present without InContent")
+	}
+	if _, ok := got.Highlight.Fields["title"]; !ok {
+		t.Error("title highlight missing")
+	}
+	if len(got.Query.Bool.Filter) != 1 || got.Query.Bool.Filter[0].Term["tenantId"] != int64(1) {
+		t.Errorf("tenant filter = %+v, want numeric tenantId=1", got.Query.Bool.Filter)
+	}
+}
+
+func TestESSearchRequestContentFields(t *testing.T) {
+	got := esSearchRequest(SearchQuery{Text: "Mahnung", InContent: true}, "")
+	mm := got.Query.Bool.Must[0].MultiMatch
+	want := []string{"title^2", "document.attachment.content"}
+	if !reflect.DeepEqual(mm.Fields, want) {
+		t.Errorf("fields = %v, want %v", mm.Fields, want)
+	}
+	if _, ok := got.Highlight.Fields["document.attachment.content"]; !ok {
+		t.Error("content highlight missing with InContent")
+	}
+	if len(got.Query.Bool.Filter) != 0 {
+		t.Errorf("filter = %+v, want none without tenant/folder", got.Query.Bool.Filter)
+	}
+}
+
+func TestESSearchRequestFiltersAndLimit(t *testing.T) {
+	got := esSearchRequest(SearchQuery{
+		Text:       "Storchen",
+		FolderID:   "649",
+		Extensions: []string{".PDF", "pdf", "docx"},
+		Limit:      999,
+	}, "42")
+	if got.Size != maxESLimit {
+		t.Errorf("size = %d, want cap %d", got.Size, maxESLimit)
+	}
+	var tenant, folder, wildcards int
+	for _, f := range got.Query.Bool.Filter {
+		switch {
+		case f.Term != nil && f.Term["tenantId"] != nil:
+			tenant++
+		case f.Term != nil && f.Term["folders.folderId"] != nil:
+			folder++
+			if f.Term["folders.folderId"] != "649" {
+				t.Errorf("folder filter = %+v", f.Term)
+			}
+		case f.Wildcard != nil:
+			wildcards++
+		}
+	}
+	if tenant != 1 || folder != 1 {
+		t.Errorf("term filters tenant=%d folder=%d, want 1 each", tenant, folder)
+	}
+	if wildcards != 2 {
+		t.Errorf("wildcard filters = %d, want deduped PDF+docx", wildcards)
+	}
+}
+
+func TestESSearchRequestRejectsEmptyTextAtSearch(t *testing.T) {
+	s, err := NewESSearcher(ESConfig{URL: "http://localhost:9200"})
+	if err != nil {
+		t.Fatalf("NewESSearcher: %v", err)
+	}
+	if _, err := s.Search(t.Context(), SearchQuery{Text: "  "}); err == nil {
+		t.Error("empty query: want error")
+	}
+}
+
+func TestNewESSearcherRequiresURL(t *testing.T) {
+	if _, err := NewESSearcher(ESConfig{}); err == nil {
+		t.Error("empty URL: want error")
+	}
+	s, err := NewESSearcher(ESConfig{URL: "http://es:9200/"})
+	if err != nil {
+		t.Fatalf("NewESSearcher: %v", err)
+	}
+	if s.cfg.Index != defaultESIndex {
+		t.Errorf("index = %q, want %q", s.cfg.Index, defaultESIndex)
+	}
+	if s.cfg.URL != "http://es:9200" {
+		t.Errorf("url = %q, want trimmed", s.cfg.URL)
+	}
+	if s.Name() != "elasticsearch" {
+		t.Errorf("Name() = %q", s.Name())
+	}
+}
+
+func TestNormalizeExtensions(t *testing.T) {
+	got := normalizeExtensions([]string{" .PDF ", "pdf", "", "xlsx"})
+	want := []string{"pdf", "xlsx"}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("normalizeExtensions = %v, want %v", got, want)
+	}
+}
+
+func TestParseESSearchResponse(t *testing.T) {
+	raw := []byte(`{
+	  "took": 12,
+	  "hits": {
+	    "total": {"value": 2, "relation": "eq"},
+	    "hits": [
+	      {
+	        "_id": "2395",
+	        "_score": 7.31,
+	        "_source": {"id": 2395, "title": "Rechnung-4711.pdf",
+	          "folders": [{"folderId": "438", "id": 0}, {"folderId": "11", "id": 0}]},
+	        "highlight": {
+	          "title": ["<em>Rechnung</em>-4711.pdf"],
+	          "document.attachment.content": ["… Zahlung der <em>Rechnung</em> …"]
+	        }
+	      },
+	      {
+	        "_id": "2318",
+	        "_score": 6.02,
+	        "_source": {"id": 2318, "title": "Mahnung.pdf", "folders": []},
+	        "highlight": {"title": ["<em>Mahnung</em>.pdf"]}
+	      }
+	    ]
+	  }
+	}`)
+	hits, err := parseESSearchResponse(raw)
+	if err != nil {
+		t.Fatalf("parseESSearchResponse: %v", err)
+	}
+	if len(hits) != 2 {
+		t.Fatalf("hits = %d, want 2", len(hits))
+	}
+	h0 := hits[0]
+	if h0.ID != "2395" || h0.Title != "Rechnung-4711.pdf" || h0.Kind != File {
+		t.Errorf("hit0 entry = %+v", h0.Entry)
+	}
+	if h0.ParentID != "438" || !reflect.DeepEqual(h0.Path, []string{"438", "11"}) {
+		t.Errorf("hit0 path = %v parent = %q", h0.Path, h0.ParentID)
+	}
+	if h0.Score != 7.31 {
+		t.Errorf("hit0 score = %v", h0.Score)
+	}
+	if h0.Highlight != "… Zahlung der Rechnung …" {
+		t.Errorf("hit0 highlight = %q, want content fragment", h0.Highlight)
+	}
+	if hits[1].Highlight != "Mahnung.pdf" {
+		t.Errorf("hit1 highlight = %q, want title without tags", hits[1].Highlight)
+	}
+	if hits[1].ParentID != "" || len(hits[1].Path) != 0 {
+		t.Errorf("hit1 path = %v", hits[1].Path)
+	}
+}
+
+func TestESSearchRequestJSONShape(t *testing.T) {
+	got := esSearchRequest(SearchQuery{Text: "Rechnung", InContent: true}, "1")
+	b, err := json.Marshal(got)
+	if err != nil {
+		t.Fatalf("marshal: %v", err)
+	}
+	var back map[string]any
+	if err := json.Unmarshal(b, &back); err != nil {
+		t.Fatalf("unmarshal: %v", err)
+	}
+	if _, ok := back["query"].(map[string]any)["bool"]; !ok {
+		t.Errorf("query.bool missing: %s", b)
+	}
+}