Thread:Mathmagician/@comment-5014329-20130413164732/@comment-4674838-20130413170000

All wikis (not just Community Central) have an advanced search options section. When searching for pages on a wiki, those options are used to choose which namespaces you want to look in.

The search on wikia.com is different. Instead of searching for pages on a wiki, it searches for wikis on all of Wikia. Because the nature of the search is different, the concept of "namespaces" isn't applicable, so I don't think it has any advanced search options.