Here is the full list of all 31 Riddles Of The Past achievements.
Found a newspaper
Found a gas bill
They took Fred!
Found a ticket
Found an old poster
You came to the Riverside
Found a magnifying glass
Recall what happened on stadium
Found a photo album
Found heart shaped pendant
Found jack blueprint
Found a menu
Found access key
Found a folder with a card file
Found a player badge
Found football player photo
Found a dancer figure
Found a light bulb
Found Clarck's ring
Found a film
Found a red book
Found a chip
Found a burner
You've met the bartender
Recall the marriage proposal
Discovered an enemy
You found a robot blueprint
Crimes history revealed
Turned anabiosis capsule off
Remote control is lost
Evil genius is defeated!