The really thin Chinese noodles are called Rice Vermicelli or mi fen, which is a very fine type of noodles that originated from southern China.
The Rice Vermicelli are thin, brittle and white and often sold dried and in blocks.
Another really thin Chinese noodle is Glass Noodles also known as Fensi/cellophane noodles which are made from starch and even Chow Mein noodles, which are thin wheat noodles that are often used in stir fries.
But Rice Vermicelli is the most common very thin and fine thread like Chinese noodle.
There's also another noodle called Mee Sua, which is also very delicate and thin.
The rice Vermicelli noodles which are thin and delicate noodles are made from rice flour, and are essential in many Asian cuisines for dishes like salads, soups and even spring rolls, which offer a neutral base that soaks up savory flavors from ingredients like grilled meats and fresh vegetables.
Rice vermicelli noodles are also known for their light and sometimes even gluten free texture and are also prepared by soaking in hot water or a quick boil, which allows the noodles to absorb liquid and become tender and provide a balance to flavorful components.