Editing Troubleshooting of Google Vertex AI Search (section)

=== Troubleshooting: Vertex AI Discovery Engine: Search Returns No Results ===

Issue encountered when searching with keywords against a Vertex AI Discovery Engine Data Store: the query executes successfully but returns no content.

'''Symptom:'''
The API responds with empty result arrays:
<pre>
{
  "attributionToken" : "xxxx",
  "guidedSearchResult" : [],
  "summary" : [],
  "semanticState" : "DISABLED"
}
</pre>

'''Cause:''' The query syntax is correct, but the target website is outside the indexing scope of the Data Store specified by the Vertex API. For example, attempting to search <code>aaa.com</code> while the Data Store only indexes <code>example.com</code> will return no results, since the engine can only retrieve content it has actually crawled and indexed.

'''Solution:''' Verify and expand the indexed website scope:

# Navigate to https://console.cloud.google.com/gen-app-builder
# Open the Data Store referenced by your Vertex API call
# Check the configured website scope under the "Data" tab
# Confirm whether the target domain (e.g., `aaa.com`) is included

If the target domain is not covered, you must create a dedicated Data Store for it:

# In '''GCP Console → Vertex AI Search''', create a new Data Store for `aaa.com`
# Configure '''website crawling''' for that domain 

{{exclaim}} Note: Each Data Store indexes only its own configured site list — a query cannot reach content outside the Data Store's crawl scope, regardless of how correct the query syntax is.