Soft Book Card is a scratch card affixed to the back cover of English textbooks and some reference books of Vietnam Education Publishing House. On the Softbook Card there is a secret code under the silver coating used to activate the softbook version of the book on the sachmem.vn system.

Currently, the market is flooded with books of unknown origin, pirated books, and fake books. Therefore, Vietnam Education Publishing House develops a Soft Book Card application to help users initially check real/fake books before deciding to buy books through the Serial number (or S/N) on the Soft Book Card.

However, the SoftBook Card application is only a warning application, does not confirm that when the serial number (S/N) is correct, the usage code under the silver coating is valid, as the Softbook card can be counterfeited with real serial number and fake user code.