Can anyone tell me how I can tell where the bees are getting in my log home?

I live in the woods in a log home, I have big yellow bees, stripped, getting in. They can not be getting in through the logs, because we have chinked the inside and have caulked and sealed the outside.Can anyone tell me how I can tell where the bees are getting in my log home?
Can't really say I've experienced this...but how many bees are we talking about? If its just a few, then its probably through an open door every now and then. If its a lot...possibly a bad window seal....or maybe a hole in the window frame (sometimes there are holes in the bottom of the frame for drainage if it rains a lot)....or maybe a chimney/fireplace? How about the attic, if you have one? Light fixtures sometimes have holes, if its recessed lighting. Not sure how your house is set up or how old it is. Check outside of your home....wait until its very quiet at night and go out...do a perimiter check of your home and try to listen for buzzing. I'm serious...sometimes that's the only way when you can't actually see them or how they're getting in. In some homes (we used to have this) they have air holes (often with a screen over them) to give some air to the roof or attic. Not sure you have an attic though, if its a log home. How about the floor boards? Just some ideas. Good luck.