Here is the full list of all 77 Elena's Journal: To Atlantis achievements.
Fill up the museum exhibition.
Collect diamonds.
Complete minigames in the Atlantis location.
Complete minigames in the Excavations location.
Complete minigames in the Daphne location.
Complete minigames in the Public Library location.
Complete minigames in the Petunia's Confectionery location.
Complete minigames in the University location.
Replay levels
Give out swords.
Give out brushes.
Pass the wrench.
Sell ship miniature.
Serve coffee.
Sell pens and ink pens.
Finish all levels in the Atlantis location.
Finish all levels in the Excavations location.
Finish all levels in the Daphne location.
Finish all levels in the Public Library location.
Finish all levels in the Petunia's Confectionery location.
Finish all levels in the University location.
Get 'full order' bonus.
Get 'quick service' bonus.
Get 'all clean' bonus.
Watch all in-game cutscenes.
Checkout customers with 5 hearts.
Complete levels with 3 stars.
Find Zeno.
Don't serve customers. Yes, it's rude.
Collect cups by completing side objectives.
Complete levels with at least 1 star.