I'm getting frustrated! lol
I got the keep them in thing!
There's no "technique" to getting them back?
When you do find them do you use a net? or food?
I think the best approach IS the keep them in thing... as suggested, look to making every entry/exit to your home via a double door. Our front door has a catch space before the exterior iron grille door. Our back door leads into their enclosure and then there is the door to the garage. You could just aim to enter and leave home via the garage to help with that.
Never ever let your cat walk through the entry/exit doors, best approach is to always put them (with walking jacket already on) into a crate and carry through the door. Then you get the bonus of them loving the crate as it is associated with a good thing.
But yes, accidents happen. Your location seems different by being more secluded so the usual flyers and checking with neighbors may not be enough. I'd probably get a couple of larger humane traps to keep in storage in case you need them, but maybe also look into tracking dogs. They will just need an item with scent like a cat bed or something...
My stories probably aren't so relevant to you, as I live in a large city. Loads of flyers everywhere and using findtoto.com helped me in those cases.