The basic search function searches the fields listed below. Advanced Search functions differently.

Products/Variants:

• Name
• SKU
• Manufacturer's Part number
• Description

Entities:

• Name

Search can be used on your site 2 ways: 

Control: 
You can embed the basic search control into your skin wherever you would like the search box to appear, such as: 

Basic Search Page Link: 
You can link directly to the /search.aspx page from within the Topic: Template.TopNavigation 

Additional Notes: 
Setting: SearchDescriptionsByDefault allows the search to include product descriptions as well.

By default, search terms that customers look for on your site are not logged.  You can set the Search_LogSearches Setting to true to record those searches in the SearchLog table in your store's database.  Those values can be queried out using a custom report.

You can use an XmlPackage based display for the Basic Search (and the Advanced Search), selectable with the Settings: XmlPackage.SearchPage and XmlPackage.SearchAdvPage 

It is recommended that Full Text Search not be enabled in order for the Basic Search to operate effectively. You may want to experiment with FTS enabled/disabled to determine your preferred behavior.