I can't find the original "Lanting Preface". How did the printed matter come from?

Everyone who studies calligraphy knows that Wang Xizhi has no original works in the world. The prototype of this work is the Dragon Book of the Preface to the Lanting Pavilion (a hook copy of Feng Chengsu, a calligrapher in the Tang Dynasty, now in the Palace Museum, which is the best copy of the Preface to the Lanting Pavilion). It is said that the manuscript was buried in Zhaoling of Emperor Taizong of Tang Dynasty, which has not been confirmed or unearthed yet. If you want a beautiful Preface to Lanting, you can buy it on Taobao.