BuddyPress Global Search is a plugin that can create a unified search facility for your entire BuddyPress site, adding all the BuddyPress components into the search if desired. It extends the functionality of the existing site search.
Search
BP Profile Search is a plugin that can integrate an advanced profile search feature into your Members Directory page that searches through all or selected profile fields.
BP Search is a BuddyPress plugin that adds a dynamic drop down lookup list to the search box on the BuddyPress Members page.