The magnifying glass will buzz when it gets close something interesting.
If you hold the magnifying glass still for a few seconds, a clue will turn
up.

* Use the crowbar on the box 
* Use the magnifying glass on the bottle (clue #1) 
* Use the crowbar on the cloth bundle 
* Use the magnifying glass on the gun (clue #2) 
* Use the magnifying glass on the stained handkerchief (clue #3) 
* Use the magnifying glass on the ashtray (clue #4) 
* Use the magnifying glass on the upper right corner of the cloth (clue #5) 
* Use the magnifying glass on the upper left corner of the cloth (clue #6)