Here is the full list of all 20 Wanna Survive achievements.
Reach North City
Complete all stages in the game
Complete Man's storyline
Complete Doc's storyline
Have all characters join your party
Kill 2 zombies with a single spear attack
Complete Gramps' storyline
Complete Father's storyline
Kill 4 zombies with a single shot
Kill 8 units with a single explosion
Complete Dog's storyline
Kill 4 units with a single explosion
Kill 1 zombie by pushing a unit
Kill 3 units by knocking back an explosive unit
Have all characters reach the end
Complete Kid's storyline
Complete Boxer's storyline
Complete Girl's storyline
Complete all stages without taking any damage
Leave the Store with nothing unsearched