The thing to do in the Airbnb search, @George1488 will be to use the map. That way you can work on filtering to the degree of seclusion you want. Put "2" in number of guests. Choose "entire place".
What I would do, though, is use google. It will give you more hits to wade through, but you can enter "romantic Airbnb for two secluded Pennsylvania" and maybe find the perfect spot.
Or a Pennsylvania host might happen to answer here, but I wouldn't count on that. This is a global community centre. 🙂