Ajax Search Pro for WordPress was designed to boost the user search experience to the maximum. It provides a live ajax search, which makes the wordpress search experience more confortable. The results are presented with images (if any found), so they look more attractive and less flat. The search works with mobile devices, let it be Android or IOS powered. As of version 3.1 (2014 sep. 19) the search can override the default wordpress search results – so the ajax functionality is extended. The search can return posts, custom post types (like WooCommerce products, BBPress forums, topics, replies), Categories, custom taxonomy terms, buddypress users, buddypress gorups and buddypress activities as results.

Demo: http://codecanyon.net/item/ajax-search-pro-for-wordpress-live-search-plugin/3357410