love story vs story

love story and story both are nouns.

Word	Noun	Adjective	Verb	Adverb
love story	Yes	No	No	No
story	Yes	No	No	No

As nouns, story is a hypernym of love story; that is, story is a word with a broader meaning than love story:

love story (noun)	story (noun)
a story dealing with love	a structure consisting of a room or set of rooms at a single position along a vertical scale
	a piece of fiction that narrates a chain of related events
	a short account of the news
	a trivial lie
	a message that tells the particulars of an act or occurrence or course of events; presented in writing or drama or cinema or as a radio or television program
	a record or narrative description of past events