When there was no message, staff members simply recommended their favorite books.

"Sometimes, we find ourselves picking two or three books whose total price surpasses the limit of 88 yuan, but if it's a good match we will not change our choice to meet the price requirement. We lose money in these cases, but otherwise, our choices can be very limited. So we sometimes adjust the price to increase the range from which to choose," Lyu says.

However, the blind-picking has increased book sales overall, especially those often overlooked by readers.

A reader with the user name, "Just-starting-working-yet-already-hating-it A Yue", posted on her micro blog that she received Last Evenings on Earth by Chilean writer Roberto Bolano Avalos.

"I just opened the box to see what I got before walking out but was immediately attracted by Last Evenings on Earth so that I took it with me. I read the book on the bus and decided to buy the author's other works such as 2666 and The Wild Detectives. … Without 'blind pick', I would have never bought a book by a Chilean writer."

Lyu and his colleagues are happy to see such good results, and they also realize that the bookstore has been gradually turning into "Namiya General Store" in Japanese writer Keigo Higashino's The Miracles of the Namiya General Store, which offers solutions and comfort to lost souls.

Some buyers getting in touch are experiencing a very difficult time in their lives, such as losing a family member, ending a long-term relationship, facing complicated family problems, or finding out their sexual orientation is unacceptable to parents or classmates.

"They will say in the messages that they don't know what to do. In summer, a lot of college graduates told us they felt lost, worried or depressed because they couldn't find a job," Lyu says.

"We are like a tree hole, to which you can say anything you want. We're glad that with books we can offer some help. Unlike films, books give readers more time to think and to heal themselves," he says.

"We all joke that if we didn't sell books we should become psychoanalysts in the future."

Contact the writer at yangyangs@chinadaily.com.cn