What ancient books have not been handed down?

The original of Yongle Dadian has not been found yet. "Yongle Dadian" was compiled by the emperor at that time, and I liked his book very much. Because the project of this book was too big, it would be a huge project to print it directly, so there was actually no manuscript at first, only one original.

Later, because of a big fire, the emperor ordered his ministers to extract it. The emperor cherished this book very much. He often used it, but then there was a fire, and the book was in the fire. At that time, the ministers were ordered to save this book first, which shows that this book is very important in the emperor's mind. Later, ministers saved the book. In order to avoid this situation, the emperor began to ask ministers to extract a copy, which was basically consistent with the original at that time. Then the emperor began to use this copy, and then put the original in the place where he put the book, but then the book disappeared inexplicably, no one knew where the book went, and then it was never found.

At that time, it was speculated that the book Yongle Dadian was lost in the war because of the war. The book Yongle Dadian is very complete, so many people want to own it. But later, because the country was in war, many cultural relics in our family lacked protection psychology, which led to many cultural relics disappearing. At that time, the book Yongle Dadian may have disappeared in the war, and then people never found it again.

In a word, after the book Yongle Dadian disappeared, people never found it again.