Get more appropriate results using Google’s site: prefix
The following describes searching the WordPress web site but can be applied to any site.
I use the WordPress web site on a daily basis for researching tools and techniques for web development. I often look at the plugin repository to see if a tool is already available before heading off to develop new functionality.
Unfortunately, I find the search results from within the WordPress plugins area severely lacking. Luckily, you can use a prefix in a Google search to get better results.
Any Google search can be restricted to a specific domain name or even smaller subset of a web site. In our case, I want to search the WordPress web site’s plugin area. The plugins are located at http://wordpress.org/extend/plugins.
To execute a search you just type your search criteria followed by the site: prefix with the domain location you want to search.
Example:
related posts site:http://wordpress.org/extend/plugins
This will search for “related posts” in the plugins area of the WordPress web site.