This is similar to UA filght 93 crash on 911

https://en.wikipedia.org/wiki/United_Airlines_Flight_93#Crash

you can read the "Aftermath" section following the link and see how and where human remains and other aircraft fragment were found. Flight data recorder and cockpit voice recorder were both found deep in ground.

UA 93 was a Boeing 757, much bigger than 737-800, therefore may be buried deeper. But the crash site of MU's 737 is comparably difficult to work with.