fix: Resolve issue with multi-user mode search (#1562)

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## Description
Resolve issue stopping multi-user search capability

## Type of Change
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- [ ] Bug fix (non-breaking change that fixes an issue)
- [ ] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
- [ ] Code refactoring
- [ ] Performance improvement
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## Pre-submission Checklist
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- [ ] **This PR contains minimal changes necessary to address the
issue/feature**
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cognee/api/v1/search/search.py

@@ -179,13 +179,6 @@ async def search(
         if not datasets:
             raise DatasetNotFoundError(message="No datasets found.")
 
-    graph_engine = await get_graph_engine()
-    is_empty = await graph_engine.is_empty()
-
-    if is_empty:
-        logger.warning("Search attempt on an empty knowledge graph")
-        return []
-
     filtered_search_results = await search_function(
         query_text=query_text,
         query_type=query_type,