Find the Search Administration Console (from central admin)

1. Select service applications
   
2. Select the search service application.

Find and set Crawl Rules

1. Crawl rules are located here
   
2. 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

1. This can be a bit tricky to find. Select Crawl Sources
   
2. 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):