[nibnib]

You can easily combine techniques. Send rescue dogs and handlers wherever phone signals are traced.

[deadbunny]

Having worked for companies trying to detect mobile phones this would be about as useful as guessing. Triangulating a signal (if you could even get one from under 2 tons of rubble) is not an easy task in the real world, especially one that would need to be accurate to within 1m or so.

[maxxxxx]

That's probably what they are doing. These people are not dummies that need to be lectured by some hacker news guys.