K, look under heat sources, in any open drawers, in your bed, under the bed... is the room upstairs or down? If in an enclosed area look in any small opening. If it has access to multiple rooms look in the nearest rooms in the same sort of places.
Corns (because of their lack of needing high temperatures) can live for long periods of time in your house. Put out a bottle trap in each area your snake could potentially access... but I found it just didn't work. You'll probably end up finding him/her in the randomest place ever. GOOD LUCK!