Here is the full list of all 22 Dreaming Sarah achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
Finish the game.
Find the watch.
Find the bus card.
Find the shell necklace.
Find the juice box.
Find the heart-shaped key.
Find the dead cat.
Find Blockhead.
Shrink the eye.
Help the pianist.
Find the bullet.
Find the ID card.
Discover the ancient aliens.
Find the glasses.
Find the paint bucket.
Find the magnifying glass.
Touch the moon bunny.
Find the pill.
Find the compass.
Find the hat.
Find the bag of seeds.
Find the umbrella.