Gmail has long had a robust system for searching within the subjects and bodies of your emails, now you can search inside select attachments–PDF, Word, and PowerPoint attachments are all searchable.
Prior to this update, Gmail could search inside of HTML attachments but lacked more advanced attachment querying abilities. Now when you search your Gmail account you’ll see search results for not only the subject and body contents but also the contents of popular formats like PDF and Word documents.
Don’t forget to take advantage of advanced search terms to speed up your query. If you know the information you need is in an attachment but can’t remember which email, include “has:attachment” in your search to only peek inside emails with attachments.