The problem isn't just with searching. Any time the PCs spend too much time in one place, you need to make sure time keeps moving in the rest of the world too. When the players IMC started to get too cavalier about the passage of time, I took some rather extreme steps to break them of that habit.
In this particular adventure, the PCs snuck in the back door of an underground stronghold, intending to strike by surprise. After a couple of hard fights, they holed up in a defensible room to rest and recover spells. Not smart! That lost them the advantage of surprise, and gave the enemy
eight hours to plan, scheme, and organize.
By the time they left that room, they found that
Wall of Stone and
Wall of Iron spells had been used to block off some doors and hallways, leaving them only one way to go. That remaining corridor was scattered with caltrops, and packed with mundane and magical traps. Plus, a
Guards and Wards spell was running, what with the fog and the illusions and the misdirection effects.
To add insult to injury, there was nobody left in the place. The Main Bad Guy knew he was no match for the adventurers, so he strolled out another door, taking all his bodyguards and important treasure with him. Since the PCs were sent to rescue some of his slaves, he had all the slaves butchered, and spelled out a friendly little note with their entrails.
Maybe I was a bit overdramatic, but now my party knows better than to waste time in a dungeon.
