Here is the full list of all 21 GARAGE: Bad Trip achievements.
Watch a TV show
Smash 15 vending machines
Unlock a combination lock
Pick up soap in the shower room
Find a secret passage
Find all the parts of Demikhovsky's diary
Open the shelf in the desk
Score a goal with your head
Take "heavenly" pills
Kill your first cadaver
Ride the train
Dispose of the old boss
Kill the centipede
Kill Dreadnought
Beat the game
Complete the Labyrinth Challenge
Complete the Axe-man Challenge
Complete the Skirmish Challenge
Complete the Arena Challenge
Find a condom
Kill Demikhovsky