卷 (juǎn): Originally, this referred to a roll or scroll of bamboo slips, which were the earliest books in China. Today, it means a book volume or a scroll.
帙 (zhì): This character refers to the cloth wrapper or satchel used to protect and hold a set of ancient scrolls. By extension, it also came to mean “books” or “volumes.”
浩 (hào): This means vast, grand, or immense. It's the same character used in 浩瀚 (hàohàn), meaning a vast expanse of water. It paints a picture of oceanic size.
繁 (fán): This means numerous, many, and sometimes complex or intricate.
The characters combine beautifully: `卷` and `帙` are two classical words for books, creating a compound idea of “books and texts.” `浩` (vast) and `繁` (numerous) are then used to describe them. So, literally, it translates to “Scrolls and book-wrappers are vast and numerous,” a powerful and elegant way to describe a massive collection of writings.