Thanks very much for your help. I think I may have come up with a simpler solution: Most of my spam troubles are via my old aol acct - which I still use as my primary personal email acct. I have my aol emails programmed to go to my Mac Mail app, which is where I normally retrieve them. I just went directly to the aol mail acct and found a filter setting that allows you to put just a portion of a sender's domain into a filter that will, supposedly, send the mail directly to the deleted folder. We'll see if that works.
Additionally, I realized that I can quickly remove the offending emails from the aol spam folder in my Mail app by putting the partial domain name into the search box of the spam folder, and then deleting all results. That worked well for me just now, my objective being to filter out genuine spam so that I could examine the other messages in the spam folder for any that I might actually want to save.
I hope the above might help you and/or others who encounter this problem.
Thanks again!