site:

Returns webpages that belong to the specified site.

Example

"heart disease" (site:bbc.co.uk OR site:cnn.com)

Remarks

To focus on two or more domains, use OR to group the domains. You can use site: to search for web domains, top level domains, and directories that are not more than two levels deep. You can also search for webpages that contain a specific search word on a site.