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