Sync movie from Mac to iPhone

I open Finder. Click on the name of my iPhone. Click on Movies. I see a long list of movies with check boxes next to them. None is checked, which is fine, because I don't want to clog my iPhone with all of those movies. There is an "apply" button at the bottom that I can click once I select the movies that I want. I want two specific short movies. Neither of them is in the list. Actually, I'd never want to sync any of those movies in that list to my phone, it would just clog up the phone. Where does Finder get the list of movies that you could potentially sync from Mac to iPhone if you check their boxes? How can I tell it to look in a different place on my Mac for those movies, so that I can select the ones that I actually want to sync?