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