Yes, using the Search Results Rollup feature, Bronze and above customers can modify the default search results behavior in order to "rollup" results by distinct domains, causing only the most relevant (top ranked) page to display for each domain, followed by a "more results from this domain" link.

In this manner, very large sites in your mini-portal, which may potentially overwhelm the search results for particular searches, will only display a single match, similar to any other site with a matching document. To see more results from any particular domain, user's can then click the "more results from this domain" link. If a particular search result yields multiple matches from ONLY a single domain, then the "rollup" will not occur.

To enable the Search Results Rollup feature, from the 'Customization' tab, select the 'Page Display Options' link, scroll to the 'Search Results Rollup' section, change the default setting to 'Enabled', and click 'Save Changes'.