how long ago did you loose them? If it was a matter of minutes, DO NOT life anything or displace papers, blankets etc, just incase you set the keys on top of them. DO NOT move anything just in case you accidentally cover them up. Walk with stealth and use your million dollar man vision and scan each room thoroughly.
unlesssss.... one wears their suit of lead :D
Bottom of handbag or down the sofa back.
tell your wife your out of toilet paper
Bathroom. You rushed there first thing when you tore into the house.
the last place you put it
Retrace your steps, if they're not there then look in the places where you usually keep them.