At the top of your search results page, choose "Analyze search results." Scroll down the resulting page to view vizualizations analyzing documents by source, author, funding sponsor, etc.
Clicking into any of the visualizations will give you additional information and can allow you to generate additional searches further refining your search results. As you can see in the image below if I first select Documents by Funder and then National Science Foundation I can generate a search for just those 57 documents.
