In Discover, you can browse through the What's New section or the Categories, or you can search for a specific topic or term within these sections.
When logged in to your Meta account, you can explore all of the new and trending paper feeds by searching for your specific topic of interest. Just click on the Discover section of the left navigation bar after logging in to Meta, and you’ll see an Explore Feeds search bar at the top where you can enter your terms of interest. Currently, you need to enter your full search term, as type-ahead is not yet available in Discover, but the match can come from the title, description, or any other entities that are followed in Meta's feeds.
For example, searching for "epilepsy" will return all the feeds relating to this disease currently available in Discover: