Most big European cities are served by various airports, which could all be easy - so expanding your search can Web you a greater ticket rate. I exploit Skyscanner Nearly exclusively. I’ve never heard of the ITA Matrix, just checked it out and it seemed OK but form of restricting. https://thebookmarkage.com/story19560801/details-fiction-and-how-to-find-cheap-flights-to-europe-from-the-us