sharepoint 2013 - not searching through second document library

In SharePoint 2013 - what are the steps to take in order for SharePoint search through a second document library that lives on the same site.

I went to site contents from my root location on my site collection, created a second document library, gave it a name, made sure it was searchable through advance settings, and finally attempted to query it with search.

...but for some reason it is not picking up any results when I run the query builder under search in site settings. It only likes to read my documents out of my Site Collection Documents folder...why is that?

Thanks for any tips