Troubleshooting SharePoint Document Library Search Issues

Problem Statement

When using the KQL query ContentClass:STS_List_DocumentLibrary without additional filters, some document libraries (like “Shared Documents”) are not appearing in search results, even though they exist and contain content.

Shared Documents not returning

Initial Troubleshooting Steps Taken

1. Hidden Site-Level Visibility Setting

Action: Visited https://<your-site>/_layouts/srchvis.aspx and enabled “Always index all Web Parts on this site”

Status: ✅ Enabled - Monitoring for 24-48 hours to see if this resolves the issue

Result: No effect on bringing the shared documents search result

2. Draft or Unapproved Items Check

Question: Are items in the library marked as drafts or pending approval?

Finding: ❌ Content approval is not turned on

Conclusion: This is not the cause of the issue.

3. Search Schema Configuration

Question: Are custom columns properly mapped to managed properties?

Finding: ❌ No custom columns are used in this library

Conclusion: Schema mapping is not relevant to this issue.

4. Search Scope or Result Source

Question: Is the query scoped too narrowly?

Testing: Executed query at tenant level with no success

Conclusion: Scope is not the limiting factor.

5. Direct Path Query Test

Query Used: ContentClass:STS_List_DocumentLibrary AND Path:"<library URL>", e.g. Path:‘https://contoso.sharepoint.com/sites/ProductSupport/Shared Documents’

Result: ❌ No results returned

Conclusion: Path to a custom library works but not to the OOB Documents library

Search By Path not working

Advanced Troubleshooting with PnP PowerShell

Install-Module PnP.PowerShell prior to run the script

Connect-PnPOnline -Url "https://<your-tenant>.sharepoint.com" -Interactive
Get-PnPSearchCrawlLog -Path "https://<your-site>/<library>" -StartDate "2025-10-01"

Additional Diagnostic Queries

Try these KQL queries to narrow down the issue:

// Test 1: Check if site is indexed
Path:"https://yourtenant.sharepoint.com/sites/yoursite"

// Test 2: Search for specific known document
filename:"knowndocument.docx"

// Test 3: Check all lists and libraries on site
(ContentClass:STS_List OR ContentClass:STS_List_DocumentLibrary) Path:"https://yourtenant.sharepoint.com/sites/yoursite"

// Test 4: Search by list ID (if known)
ListId:"{your-list-guid}"

Try the search api

Thanks to Beau Cameron, I tried native Search API and the data is being returned. For some reasons the library is not returned to the OOB Search experience.

https://constoso.sharepoint.com/_api/search/query?querytext='ContentClass:STS_List_DocumentLibrary AND Path:"https://contoso.sharepoint.com/sites/ProductSupport/Shared Documents"'

Library returned to Search API

Conclusion

The library Shared Documents are not searchable using KQL query ContentClass:STS_List_DocumentLibrary fromt the OOB search experience. Anyone got any ideas to resolve the issue let me know.

References