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