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