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