"Châu Đại Dương"
I have never heard the term Oceania used in the USA, where the continent seems to always be called Australia (New Zealand is part of the continent of Australia, even though it is not part of the country of Australia). Many other countries call this same continent Oceania.
"The term Oceania refers to a group of island countries and territories in the Pacific Ocean, together with the continent of Australia. Pacific islands with ties to other continents (such as Japan, Hawaii or Easter Island) are usually grouped with those continents rather than Oceania. This term is used in several different continental models instead of Australia."