You can customize ways in which the search system provides search results.
Look in the right place.
Define result sources that specify where results come from.
Tailor the look of important result types.
Craft a display template in HTML and a result type rule that controls when to use it.
Get even more relevant results.
Create query rules to promote important results, show blocks of results, and adjust ranking.
For more information, see Search in SharePoint Server 2013 (TechNet).