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