stuck on Investication 4

I found the pieces to the key but can't open the trunk. walkthrough blog is no help

I'm having the same problem and can't get any help. Walk through did not help

If you have all the pieces of the key, the key comes together as a full key and you can open the lock. Make certain it the key is all together.

still stuck on levvel 4 cant find oll the keys parts what do i do all it does i disapear

where do i find all the parts or how do i replay