POF : Personal theory confirmed, the older your account the less useful the search function
I noticed the site was forcing my search parameters to be quite broad. If I had nothing else but location I could search in 20KM, but add anything and that jumped to 100Km when I hit the button. deleted that and started a new one, and then I could search in 5KM again with other parameters filled.
so if the experience has gotten shitty over time, burn down what you have and start over.