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