Filter contacts

On the right side of the Contacts/Database page, you'll see "Filters". On the mobile app, there's a button that opens the filters.

You can filter by most things such as tags, automations, activity, lead scores etc.

You cannot filter by form submission data here.

To filter by form submission data, you will need to go to Automation Flows and use Form Submission Data as a trigger with Condition as the first step.