What I do when looking for cards or seeing about trading cards as described in your situation, I go to the Collection Summary page for the set in question and scroll down to Reports. You can then click on Members with cards from this set on their Wantlist (or For Sale/Trade list). There I can see which members have a substantial number of cards on either list (I will open two tabs, one for Wants and one for Traders so that I can see if the member with cards to trade is also looking for cards to get back from the same set). By right clicking on the ID of any member and opening it in another tab, I can see what the member has for trade or wants in that set. If it looks like a possible match, I can also go to that member's profile and use the Trade Matching to see if there is sufficient matches for a trade (and to see if he/she is likely to trade either from their profile or Last Log In date).
Seems like a bit of a long way to do things but surprisingly, it does not take that long to go through the major players. You might also find a trade partner who has cards in other sets you are looking for.
Bruno
--------
Check my Profile page to see my 2023 Goals and my Lists of sets near completion (5 cards or less) or sets getting close (less than 100 cards missing and 75% complete).
https://www.tcdb.com/Forum.cfm/Page/B/ID/0/?MODE=VIEW&ThreadID=25745&C=0