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
Craft every item you can
Buy all the multivitamins
Solve all ancient temple puzzles
Fully impress Jim
Catch a great white shark
Dig up a talisman of the gods
Find every Kamasutra page
Light all torches
Dig up a royal talisman
Complete the main story
Dig up a grand talisman
Catch a hammerhead
Buy everything from the bait shop
Dig up a gold talisman
Catch a tuna
Dig up a silver talisman
Dig up a jade talisman
Catch a seaperch
Catch a rockfish
Dig up a stone talisman