Go into your bedroom. Start a stopwatch. Then, open every drawer, making sure to riffle through the contents; check any closets including stuff hanging on the racks or in shelves; check under your bed and between the mattress/boxspring; go through the bookshelves; look through any other container that you have. Lastly, stop the watch.
There's your answer. Adjust upward or downward depending on how big/small and furnished/unfurnished the in-game room happens to be.
Go grab a stick. Start a timer to count down from 6 seconds. Swing the stick as many times as you can before the countdown stops.
See where I'm going with this?
Real life to deny EX characters cool things (which is always a bad idea) is different from "How long does this take?"/"Rules don't say, it would take X in real life, and the PCs do this for a living, so lets take off Y"/"OK"
i think the answer depends on what are you trying to accomplish? are you trying to loot the enemies and move on? or are you searching the room trying to find hidden compartments and such? the first option should take a minute or two tops if you don't stop to identify, the second will take a while because you are doing more
Actually, the rules are NOT silent there. The game does list times for removing armor, and everything bigger than a shield takes at least a minute (and I'm pretty sure undressing and dressing corpses is harder than yourself, so likely even longer), so a minute or two tops only works if the enemy didn't use armor.