Click the Settings gear to the top-right of your Inbox, then click on “Settings”
Navigate to the “Filters and Blocked Addresses” page using the tabs at the top of the Settings page
Towards the bottom, click “Create a new filter”
Fill out the form then hit search
Check for the messages you want to filter
If you would like all displayed emails filtered, click the down arrow to the right of the searchbar and click “Create filter” at the bottom of the form
If there are emails displayed you do not want filtered, click the down arrow to the right of the searchbar and modify your form entries and click “Search” again
Check the options you would like applied to the filtered emails, check the box next to “Also apply filter to matching conversations”, then click “Create filter”