DOS did not support Chinese characters, which are not in Extended ASCII.
Many companies in Taiwan developed their own IBM PC compatible traditional Chinese operating system running on DOS, which were mutually incompatible between the OS, such as Kuo Chiao (國喬) and Acer.
The developer of the Eten OS, E-TEN, earned their early profits from sales of their hardware based plug-in card based Chinese system products.
Most traditional Chinese products were compatible with the Eten OS at that time.
The Eten and other traditional Chinese OS are now used in a few DOS based POS systems.