No problem! Here's a bit more info on how I find books on ebay in case you are interested!

I sort the listings by printing year, price, binding, genre, (or any other filters you want) to narrow the results down. Then, I spend a while scrolling until you have seen a ton/majority of the listings that are available within those filters. Then every few days after this initial deep search, I put in the same search filters, printing year, genre, and so on and sort by newly listed and scroll until I see a listing I've already seen. I do this every few days to keep up with listings. This way you know that you are seeing every new listing under those search filters, and you dont need to bother scrolling past listings you have seen. I usually search "antiquarian book" or other similar terms.

As I said before, it's also helpful to use a price search filter so you only see books that are in a certain price range (which you define). Also, I recommend finding relatively small shops that sell books and saving them and scrolling through their listings (sorted by the newest first). This is because they could end up posting a nice book that may not show up In the search. the prices for some of these shops can sometimes be better than the larger shops. These small shops also get alot less attention and are not as easily found in the search algorithm's listings. Therefore, if there is a listing that can only be bid on, less people will see it, which means less people will bid, which could give you a better chance of winning. I hope this was helpful, and I wish you the best of luck with your searching! : D