Indonesian vs Asian

Indonesian and Asian both are nouns.

Word	Noun	Adjective	Verb	Adverb
Indonesian	Yes	Yes	No	No
Asian	Yes	Yes	No	No

As nouns, Asian is a hypernym of Indonesian; that is, Asian is a word with a broader meaning than Indonesian:

Other hypernyms of Indonesian include Asiatic.

Indonesian (noun)	Asian (noun)
the dialect of Malay used as the national language of the Republic of Indonesia or of Malaysia	a native or inhabitant of Asia
a native or inhabitant of Indonesia

Indonesian (adjective)	Asian (adjective)
of or relating to or characteristic of Indonesia or its people or languages	of or relating to or characteristic of Asia or the peoples of Asia or their languages or culture