Most of the time you should check closets or anywhere dark with junk/clutter in them, look in the shoes, boxes, anything that the snake can squeeze into, under refridgerators or places that would hold heat-some parts of the US are warming up so that may be out the window soon. They can fit in some very tight spots, so if you had a hole or crack in the wall/doors/windows left open that lead to the outside thats not good.
You could try this, get a secure cage and putting f/t food inside the cage in the room that the snake escaped in around sunset. Leave it like this until around 2 or 3 am no peeking, sometimes it coaxes them out of hiding and they will be trying to get into the cage for the food. Dont forget to sneak up, burst in and turn the lights on quick.
If nothing else you might just be walking around and stumble on the snake one day out of the blue. If you have cats and dogs dont ignore any scratching/barking at a strange thing like under the kitchen oven. Had a chihuahua that was good at finding escapees for me. He would sit where he saw then a cry until I checked it out-miss that little rat dog.
I had a WC gopher escape when I was a little boy, a door was left open and I did not see the snake again. We lived in a culdesac and about 3 years later I was walking across the steet that lead to a large open field outside of our culdeseac and I saw her flat on the road. . .the snake had a hiding place around our house to the field to hunt for 3 years. Just amazed me, I felt bad but what can you do. I knew it was the snake because the area was devoloped, I grew up there and had never seen a single snake in the area besides the one that was flat moving in the direction fom the culdesac to the field that was a clearly "they" gopher.
good luck.