Traditional Women's Hairstyles of the North
Aside from the ao tu than, the traditional "look" of Northern girls included a khan dong and a khan mo qua.
The khan dong is a black piece of fabric wrapped around a girl's long hair so that it forms a tube around the hair. The fabric-entubed hair is wrapped around the crown of the head. Usually, the girl's hair is a little bit longer than the khan dong, forming a skinny, wispy ponytail sticking out of the khan dong. This ponytail is left dangling down from the khan dong on one side of the head. The Vietnamese call this hairstyle toc duoi ga because the ponytail resembles a rooster's tail (toc duoi ga means chicken- or rooster-tailed hair). For formal occasions, Vietnamese girls often used khan dong made of black velvet.
Instead of the rooster-tailed hair, they would pin the extra hair down and cover their heads with a khan mo qua, meaning crow's beak kerchief. A khan mo qua is a black, square piece of heavy fabric. It is folded in half into a triangle and worn over the khan dong to cover the hair. The long side of the triangle is placed above the forehead while the two corner of the long side are tied at the nape of the neck (like the American bandana and kerchiefs). Because the khan mo qua is made of heavy, stiff fabric, the long side the of the triangle, or the folded edge, sticks out in front of the forehead in a point, sharp as a crow's beak.