Cook noodles according to package instructions. Drain and soak in ice water.
Heat vegetable oil in a large pan or wok over medium heat. Add carrots and bell pepper, cooking until they soften, 5-10 minutes. Stir frequently.
Add cabbage and zucchini to the pan, cooking until they shrink, about 5 minutes. Stir frequently.
Drain noodles and add them to the pan, mixing with the other ingredients.
Add soy sauce and oyster sauce to the pan. Stir until well-mixed. Serve immediately.