Running around in the grass won’t get you a Zorua. You need to use the Dex Nav. I’m assuming you don’t know how to find Pokémon like this, so I’ll try to explain it. First, you’ll need to open the Dex Nav. Press the icon on the bottom screen that has a Pikachu and a red Poke Ball shape. To get a Zorua, run around in route 1 until a Pokémon appears (you’ll hear the Pokémon’s cry and a patch of grass will shake). Check what Pokémon it is by pressing the red circle on the bottom screen. If it is a Zorua, sneak up to it by moving your character slowly. If it isn’t, make the Pokémon run away by walking/running/biking when you’re close to it. Then go back out of the route, back in the route, and run around until another dex nav Pokémon appears.