The Qiang "Kouxian" is a folk musical instrument invented by the Qiang women who rub the hemp rope while resting during the long-term production and labor. Made of local July bamboo, it has a unique tone and is very popular among Qiang women. With the development of society, the primitive life of the Qiang people has been impacted by modern civilization. At present, there are only a handful of people who can skillfully make and play this musical instrument, and very few of the older generation can pull the strings. As a unique musical instrument of the Qiang people, the mouth string is facing the fate of being lost.

As the inheritor of oral strings, old man Wang Qingmei has been fond of oral strings since he was a child. He was "immersed" in the sound of his playing and was taught by his mother. His mother's mother was also a good player. At the age of 11 and 12, he was able to play music alone. Every time she heard the beautiful melody of the mouth string, the old man felt the love and shock from the heart. The old man said: "When I was a child, almost everyone in the stockade, whether it was a girl or a young wife or a white-haired old lady, would play the chords. In the fields of labor, the front yard of the slack farm, when there was free time, they would come together in twos and threes or Play the chords alone."

The mouth string is also a medium for young men and women of the Qiang nationality to fall in love. The young man often makes a good mouth string and sends it to the woman as a token of love. "If the girl likes a guy, she will play the song "The Qiang Guy is So Smart" for him." As he was speaking, the old man took out his chord and began to play it to the reporter. Listening to the graceful melody, the scene of "the middle of the small bamboo pieces is empty, the hemp rope is pulled and the ding-dong is played, the front of the house and the back of the house, and the spring breeze rises on the eve of the flower". Whenever the stockade holds events or traditional festivals, the voice of the old man can be heard.

The mouth string is more than 10 centimeters long and is shaped like a reed in a sheng pipe. A small hole is drilled at each end and tied with hemp rope. The rear hole is connected to the main pipe to protect the mouth string. Scales and melody are formed according to the change of the traction force and the shape of the mouth, the size of the breath and the position of the lips and tongue. The change of the accent string depends entirely on the strength of the player pulling the twine, the position where the tongue touches the reed, the size of the mouth, and the strength of the airflow in the mouth. It is difficult to play, and the methods and techniques are very difficult to master.

Although the old man Wang Qingmei is almost old and rare, in order to pass on the unique intangible culture of the Qiang people, the old man has been teaching the playing methods and skills of oral strings to those who love oral strings for free, and the Qiang oral string skills cannot be broken.