[Question]: How can I quickly perform searches using keyword matching

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### Describe your problem

How can I quickly perform searches using keyword matching? Retrieval based on segment recall is too slow and unsuitable for standard search tasks. @gschmutz

The issue does not name a file, test, or entry point for keyword matching. First clarify which existing search or retrieval path should support keyword matching, then define the expected behavior and performance target before identifying the relevant implementation and tests.

Written by the indexing model from the issue text.