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