SharePoint 2013: People Search Not Working
No people show up in the people search. You have everything set up correctly for User profiles and search application.
Issue
In this case, it was that the default content access account did not have correct permissions set in the My Site service application. It was also that we didn't tell the search content sources that there was a My Site. We also added a crawl rule, but we suspect this was overkill and would have worked with the first two steps.
Resolution
Set the permissions for the search crawler to Retrieve People Data. Go into Application Management -> Manage Service Applications page. Highlight the User Profile Service Application line. In the ribbon, click on Administrators. Add the Default content access account (check what it is on the front page of the Search Administration page) and make sure that Retrieve People Data for Search Crawlers is checked. Click on OK.
Make sure you type the sharepoint://hostname into the content sources. This tells the search that this is not just content - it is a My Site service app. If you don't add it, but just list the URL of the My Site Host, the crawler will crawl the content, but not the profiles.
Create a crawl rule. Go to Search Administration -> Crawl Rules -> Add Crawl Rule. In the Path box, type sharepoint://<hostname>, where <hostname> is the URL for the Web application where you deployed the My Sites site collection. Do a full crawl.
MS Article
http://technet.microsoft.com/en-us/library/hh582311.aspx
Note: We resolved the issue by above Method. If you find a different solution, please report it as a comment to this post. This will be useful to SharePoint Community. Be sure to double-verify it: undo your solution and verify that the problem comes back, then redo it and verify that the problem goes away.