You are not going to accomplish that using a random selection of textbooks. It doesn’t even look like there are that many textbooks in these piles. Realistically, you’d probably have better luck asking students taking intro-level courses to donate their old text books, or just pirating the textbooks you need

I’m guessing that the big books are old collections of scientific journals. Depending on the journal, you could have multiple of those tomes per year. These days scientists access journals digitally, so there’s little benefit to keeping the physical copies around in most cases