red raspberry vs raspberry bush

red raspberry and raspberry bush both are nouns.

Word	Noun	Adjective	Verb	Adverb
red raspberry	Yes	No	No	No
raspberry bush	Yes	No	No	No

As nouns, raspberry bush is a hypernym of red raspberry; that is, raspberry bush is a word with a broader meaning than red raspberry:

red raspberry: any of several raspberries bearing red fruit
raspberry bush: woody brambles bearing usually red but sometimes black or yellow fruits that separate from the receptacle when ripe and are rounder and smaller than blackberries

Other hypernyms of red raspberry include raspberry.

red raspberry (noun)	raspberry bush (noun)
any of several raspberries bearing red fruit	woody brambles bearing usually red but sometimes black or yellow fruits that separate from the receptacle when ripe and are rounder and smaller than blackberries