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.
Shrink the eye.
Find the paint bucket.
Find the pill.
Find the juice box.
Find the dead cat.
Find the heart-shaped key.
Find the shell necklace.
Find Blockhead.
Help the pianist.
Discover the ancient aliens.
Find the bullet.
Touch the moon bunny.
Find the magnifying glass.
Find the ID card.
Find the glasses.
Find the compass.
Find the bag of seeds.
Find the hat.
Find the umbrella.