Find the Search Administration Console (from central admin)
Select service applications
Select the search service application.
Find and set Crawl Rules
Crawl rules are located here
Crawl Rules can be used to Include or Exclude. In the following example, there are three rules, used as filters (to exclude):
Force an incremental or full crawl
This can be a bit tricky to find. Select Crawl Sources
There should be only one content source present, unless you have set up others. Click the dropdown next to it – you’ll see options to crawl (which will be grayed out if a crawl is presently running):