I'm trying to tell someone that I've learned a lot from a set of videos and books: "Thanks a lot for your excellent books and videos. I have learned a lot from them." and so my attempted translation was: "Muchas gracias para tus libros y videos excelentes. He aprendido mucho de los."
Is this correct? Can I end a sentence with "de los" like this to mean "from them"? For some reason, something about it seemed off ... if this is incorrect, what would be the best way to translate this type of sentence - i.e. "I have _ from them"?