That is because the main features of Yu Shu are relatively rare. It should be that the circulation of Yu Shinan's works is becoming increasingly rare. In ancient times, the most economical and widespread way of spreading calligraphy was stele rubbing. However, Yu Shinan had very few calligraphy and stele works. Only the "Confucius Temple Stele" has been handed down. Unfortunately, the original stele was destroyed shortly after it was erected. By the Song Dynasty, the original rubbings of the "Confucius Temple Stele" were already rare treasures. Therefore, Huang Tingjian, a calligrapher of the Northern Song Dynasty, lamented that "the Zhenguan engraving of Yu Shu's temple can only be purchased with a thousand taels of gold." This shows that the spread of his works is rare. To this day, no reliable calligraphy of Yu's calligraphy has survived, and only one original stone rubbing of "Confucius's Temple Stele" has survived. However, a large number of reprinted texts have been made up, making it difficult for the world to see the true face of Yu's calligraphy. This has seriously affected Yu's calligraphy. spread.
Therefore, Yu Shinan’s copybooks have basically not been circulated.