Rinse bean sprouts in cold water and discard any bad sprouts.
Bring a pot of lightly salted water to a boil over high heat. Plunge bean sprouts and cabbage into the pot and let boil for 3 to 4 minutes.
Meanwhile, whisk rice vinegar, sesame oil, sugar, sesame seeds, fish sauce, and garlic together in a bowl for dressing.
Drain water from the pot and run cold water on the sprouts for 1 to 2 minutes. Squeeze bean sprouts with your hands to remove excess water. Place sprouts and cabbage into a mixing bowl and add carrot, green onion, and dressing; mix well.
