Searches enable you to easily find things on the web through predefined search scopes. This frees you from typing repetitive parts of search queries. For example, you may add a search scope for "Photoshop How-Tos". When you type "outline text" to it, Google auto-opens and performs a search for "How to outline text in Photoshop". Or you may add a search scope for "Stackoverflow" that will add "site:stackoverflow.com" to your queries and perform a search on that site only.
Adding, Updating, Deleting Search Scopes
Use the Manage Search Scopes menu to add / delete search scopes and edit their settings. It can be accessed via the Searches tab.
Use the Query Template option to set a template for generating search queries. The template is just a regular text line with %QUERY% placeholder in it. When you type a query on the Searches tab, the %QUERY% will be replaced with it and the resulting search query will be executed. For example, if you use "How to %QUERY% in Photoshop" template, and type "outline text" on the Searches tab, then this will perform the "How to outline text in Photoshop" search.
Use the Site Filter option to perform searches on a specific site only.
Also you can set the Images type to perform searches through images.
Searches can be performed using the Searches tab. Just move the cursor over the tab, click on a scope you want to search through and type your query.