Here is the full list of all 21 Treasure of Nadia achievements. It takes around 40-50 hours to unlock all of the achievements on Windows.
Find everything in the game
Solve all ancient temple puzzles
Buy all the multivitamins
Find every Kamasutra page
Craft every item you can
Dig up a talisman of the gods
Fully impress Jim
Light all torches
Complete the main story
Dig up a royal talisman
Dig up a grand talisman
Buy everything from the bait shop
Catch a great white shark
Dig up a gold talisman
Catch a tuna
Catch a hammerhead
Dig up a silver talisman
Dig up a jade talisman
Catch a rockfish
Catch a seaperch
Dig up a stone talisman