1. Cook the Lo Mein noodles according to the package instructions. Drain and set aside.
2. Heat the vegetable oil in a wok over medium-high heat. Add the garlic and onion, and stir-fry for 2 minutes.
3. Add the red bell pepper, carrot, and snow peas. Stir-fry for another 3-4 minutes until the vegetables are tender-crisp.
4. Add the cooked noodles to the wok. Pour in the soy sauce, oyster sauce, fish sauce, brown sugar, and chili flakes. Toss everything together until well combined and heated through.
5. Remove from heat and stir in the lime juice and chopped cilantro. Serve hot.