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