Replace a standard search widget with Advance Search and you will be able to filter results by many parameters ( blog, category, post author ) plus you can customize almost everything.
Category: "Widget Plugins"
This plugin allows you to add a "Nivo Slider" slideshow widget anywhere you want in your site.
This plugin allows your users and guests to choose the skin they like for each blog. It also displays a list or a dropdown menu of all available skins, just like in b2evo 1.x.
This widget allows you to put a Google FriendConnect members widget in b2evolution. People can join your site and see who else has joined.
This plugin allows integrating Flickr images into your blog.