Name: Better Search
Product info page: http://ajaydsouza.com/wordpress/plugins/better-search/
WordPress Extend Page: http://wordpress.org/extend/plugins/better-search/
The default WordPress search is limited because it doesn't give you results based on the title or content of the post, but by date.
Better Search replaces the default WordPress search engine with a more powerful search engine. Visitors will find more relevant search results of search terms. You can fine tune results by giving the title or the content more weighting.
Better Search supports templates for perfect integration into your blog template. Template for Twenty Eleven theme included in the package.
Additionally, the plugin will track the searches and allow you to present a "search heatmap" of the most popular searches. Support for WordPress widgets will allow you to easily add this heatmap to your theme's sidebar or footer.
* Updates for better search template compatibility. New template included in this release
* Quick links added in Plugins page in WP-Admin
* Relevance score is now displayed as a percentage
* Fixed: Daily search terms were not being cleared
* Modified: Default search colours for the heatmap are grey and black instead of blue and red
* Modified: Plugin will not add a link to Better Search homepage by default
* Modified: New WordPress widget to display the popular searches in your sidebar
* Added: New template file based on Twenty Eleven WordPress theme