"Following the reform and opening-up of the country after 1978, a large number of domestic and foreign literature books were published. Whenever the new books were sold out, people would flock to the secondhand bookstores to try their luck."

Running a bookstore might seem hardly exciting, but Zhu claims he is never bored. Besides categorizing the books on the shelves, the retiree also has to spend considerable amounts of time curating his collection and appraising purchases before setting a reasonable resale price.

The fact that Xiaozhu's Bookstore has been in business for more than a decade speaks volumes about its clout with local readers. This was also evidenced by how quickly business returned to normal following its temporary closure because of COVID-19. Today, it welcomes about 100 customers every day.

Among Zhu's regular customers is Hu Yongchu, a doctor at the anesthesia department of Shanghai Changzheng Hospital.

"Many forgotten treasures can be found between the tattered pages of used books," says Hu, who buys mostly medical titles.

"I do not merely obtain knowledge from the books. Oftentimes, I would get autographs, notes or sketches on the pages created by previous owners who are renowned experts in the industry," he says.

This was certainly the case for Zhu Nan. While searching for books by the late Feng Chengjun, an expert in East-West communications, Zhu chanced upon a 1935 translated edition of the book Timurid Empire in an online secondhand bookstore.