alphabet soup vs potpourri

alphabet soup and potpourri both are nouns.

Word	Noun	Adjective	Verb	Adverb
alphabet soup	Yes	No	No	No
potpourri	Yes	No	No	No

As nouns, potpourri is a hypernym of alphabet soup; that is, potpourri is a word with a broader meaning than alphabet soup:

Other hypernyms of alphabet soup include assortment, miscellanea, miscellany, mixed bag, mixture, motley, salmagundi, smorgasbord, variety.

alphabet soup (noun)	potpourri (noun)
soup that contains small noodles in the shape of letters of the alphabet	a jar of mixed flower petals and spices used as perfume
a confusing assortment	a musical composition consisting of a series of songs or other musical pieces from various sources
	a collection containing a variety of sorts of things