"Comic books have become popular in recent years, first about history and gradually touching fields such as ancient poems, medicine, and science and technology," the analyst from Beijing OpenBook says.

"This kind of book is easy to follow, catering to people's fragmented reading habits, so it sells well," the analyst says.

As one of the results of the advancement of information technology and media, it seems like that people's ability to read and understand long and complicated texts has declined, Shen says.

"We must see such comic books as only being used to popularize basic knowledge rather than elaborate on profound content. Readers usually read them to relax rather than study, so in function they cannot replace normal books on the same topics," the analyst says.

Besides the best-selling lists, a lot of platforms released their lists of "good books" that highlighted major social concerns of 2021.

At its annual reading ceremony in mid-January, the Book Review Weekly of Beijing News released a list of 12 books published in China in 2021 that were "most worth reading". Targeted at the middle-income group, the weekly's list, covering 10 fields, including literature, art, history, social sciences, economy, children, education, and lifestyle, came out after rounds of discussions among 12 experts and scholars in related fields.

Among the 12 books, there are Irish writer Roddy Doyle's Paddy Clark Ha Ha Ha, Manifeste Incertain by French writer Frederic Pajak, Shaping the World by British writers Antony Gormley and Martin Gayford, The Cheese and the Worms by Italian writer Carlo Ginzburg, and Sanbu (Take a Walk) by Chinese illustrator Dawu.

The Second Shift by US writers Arlie Hochschild and Anne Machung reflects the general concern in Chinese society regarding the low birthrate and parenting.

In the last two years, the pandemic has largely restricted the physical space for people's activities and cut off connections with nature. Ouyang Ting's Beifang Youkeshu (There Is a Tree in the North) entered the list because it illustrates how people can find nature in their surroundings. The book contains the writer's observations of Beijing's natural environment and her phenological notes on parks, plants, birds, rains, clouds and wind, presenting a vibrant picture of creatures in the city throughout the four seasons of a year.

"Every spring is different. We must keep our curiosity to ask more questions, which will bring us to farther places," she said at the ceremony.