Here is the full list of all 14 Broken Pieces achievements.
Finish Broken Pieces main story
Send a signal via the communication system in the lighthouse
Uncover the Devoted secrets
Find all souvenir items
Reach the assomption church
Find the submarine on the beach
Solve the teleporting furnitures puzzle
Get levans key without getting close to the bird
Restore the additional generator in Saint Exil
Finish Broken Pieces in less than 5 ingame days
Finish all of george's tables in Saint Exil
Complete all the dream portals
Finish the game 100%
Obtain all the game's tapes