If you would normally have filed it, look at the file folders immediately in front of and behind the folder they should have been filed in. My husband has misfiled papers this way.
If the papers were in a stack and you have recently filed any other papers, look there-- you may have grabbed a bigger stack than intended. We've done this, too.
About 10 years ago I quickly stashed away a tanzanite necklace as we were heading out the door for a vacation.
I still can't remember were I put it.
Thanks It's actually been a few years now that they've been missing :/ And I've torn apart all the places (looked in books/behind everything)....sigh.
Have you ever hidden any papers or other valuables in the freezer?
try looking in the bookcase between the books.