Question

why veitnam and cambodia known as indo china

Answer 1

Indo China is a plate which lies indian ocean and it comprise of three countries veitnam Cambodia and laos

Answer 2

Vietnam, Cambodia and loas are collectively known as Indo China because of the following reasons-
As Chinese rule the country for many years so there is a Chinese influence.
and these are under Chinese shadow for a long time
They also are under India and China proximity.
Indo China
In 1887 Indo China was formed.

Hope it will rocked with your question

###@####