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