flowering shrub vs bush

flowering shrub and bush both are nouns.

Word	Noun	Adjective	Verb	Adverb
flowering shrub	Yes	No	No	No
bush	Yes	Yes	Yes	No

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

Other hypernyms of flowering shrub include shrub.

flowering shrub (noun)	bush (noun)
shrub noted primarily for its flowers	hair growing in the pubic area
	dense vegetation consisting of stunted trees or bushes
	a large wilderness area
	a low woody perennial plant usually having several major stems

flowering shrub (adjective)	bush (adjective)
	not of the highest quality or sophistication

flowering shrub (verb)	bush (verb)
	provide with a bushing