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