How to return only PDF and Word files?

I have a search engine crawling the whole site. On some pages of the site, there are links to PDF or Word files.

How can I only get the PDF or Word files in my search results? Or can I do a faceted search for PDF and Word files?

Does the crawler currently index the PDF and Word files already, or are you also trying to figure out how to grab them?

The crawler has indexed the files already. All the files’ url starts with /-/media/files.