A customer checks out a book in a Shanghai bookstore. Photo: IC

With the approach of World Book Day on Friday, some Chinese online book stores have launched a "blind box" for books, attracting so many consumers that supply has fallen far short of demand. The idea to combine books and blind boxes - which contain an assortment of goods that remain a mystery to the purchaser until they are opened -  is being hailed as a way to rescue print books.

Some websites have launched blind book boxes on different themes such as "gourmets who are not lonely" and "what to do with the ashes of an enemy." Each box contains books and a variety of stationery products such as pens, notebooks and bags, the China News Service has reported.

The mysterious blind boxes have attracted the attention of consumers, leading to orders far surpassing the stores' inventories.

One online store for a publishing house on e-commerce platform Taobao is selling blind boxes containing classic English novels such as A Tale of Two Cities and Wuthering Heights. Each box contains 10 books and costs 100 yuan ($15.4)

One employee of the publisher told the Global Times that the items in the blind boxes are randomly picked and customers can leave a message about which books they want but the company makes no promises that they will get what they want.

Many of the comments from customers who have bought the blind boxes say that they enjoyed the excitement that came with opening the boxes and were pleasantly surprised by their contents. 

"This is the charm of blind boxes," one netizen wrote.

Some bookstores in China, like those ine Zhuhai bookstore in South China's Guangdong Province and those inthe Baotou bookstore in North China's Inner Mongolia Autonomous Region, have also put their bestsellers in boxes, each of which are is priced from 59 yuan to 99 yuan, according to a Sina News report.

Some customers have also expressed dissatisfaction with their purchases , saying that the quality of the books was not up to par and that publishers should focus more on the quality instead of creative marketing methods.