The search configuration allows you to customize the database used for indexed searches.  You can use this to adjust usernames that are used to find the VFS areas to index, as well as configuring your own custom database to hold the search criteria.  CrushFTP will periodically keep the search DB records updated, as well as tracking renames, deletes, and uploads directly in the search DB.  The list of usernames are empty by default, and the search DB does not operate then.