I have two list A and B.In list A, I have some movies which are also part of list B. I'd like to know if there is an easy way to have:List Result = List Movies A - List Movies A part of List Movies B
If I understand you correctly, this is definitely what Advanced Title Search can do by Including list A and Excluding list B.
Atop nearly every IMDb page is a search box with a dropdown menu to the right, with default All. At the bottom of that dropdown is Advanced Search. That page has 5 selections, and the top left says Advanced Title Search, which takes you here: https://www.imdb.com/search/title
Scroll down to the bottom of the page, and find the Include and Exclude boxes. You'll see your lists there.