First of all, it is not called Siku Wushu, but Sikuquanshu.
"Sikuquanshu" is the largest series of books in Chinese history organized by Emperor Qianlong himself under the background of "literary prison". It started in 1772 and took ten years to compile. The series of books is divided into four parts: Jing, Shi, Zi and Ji, hence the name Siku. According to the collection of Wenjin Pavilion, the book contains a total of 3,503 types of ancient books, 79,337 volumes, and is bound into more than 36,000 volumes. It preserves a wealth of documentary materials, but more books were destroyed during the compilation process. The name "Siku" refers to the fact that the official collection of books in the early Tang Dynasty was divided into four libraries of classics and history, known as the "Sibu Kushu", or "the books of the Four Kus". The four-dividing method of classics and history is the main method of classifying ancient books. It basically covers all ancient books, so it is called "the whole book".
If you are asking about the Four Books and the Five Classics, it is the collective name of the Four Books and the Five Classics, which are the classic books of Chinese Confucianism. The Four Books refer to the Analects of Confucius, Mencius, Great Learning, and Doctrine of the Mean; while the Five Classics refer to the Book of Songs, Shangshu, Book of Rites, Zhouyi, and Spring and Autumn Annals, referred to as "Poems, Books, Rites, and Changes". , Spring and Autumn"