@Julie685 , I understand your frustration as I've experienced the exact same thing. Algorithms can be very successful in targeting and directing website users, but I strongly believe that AirBnB is doing a real disservice to travelers when they engage in this practice.
When you enter a specific destination, it means that you don't want to look at properties 15-20 miles away. You know where you want to be, and AirBnB should show you properties that conform to your search.
This practice is actually a disservice to both hosts and guests. I'm not sure why the algorithm works this way and why they continue to use it this way, but that's how it is.
I would also note that I always check my own listing from another browser, and not signed in to my AirBnB account. I feel that I get a more accurate search placement result that way. When I'm signed in and search for my own listing as a traveler, it always shows up very near the top of the search. When I'm not signed in, the result is very different, with a spot that varies, but is usually much farther down the page.
A great way to make hosts feel good (if signed in and searching), but apparently a lie. Go figure.