When searching for movie adaptations of graphic novels or comic books, enter the search term "superhero(es)" surrounded by quotes. And be sure to limit your search to "Audio Visual + Audiobooks" in the "Limit to:" dropdown menu under the search bar.
Confused about Marvel movie rights?
Here are a couple handy guides by The Geek Twins illustrating why you do not see crossovers of certain characters. The articles attached to these illustrations give a detailed explanation about Marvel movie rights past and present.