poem vs literary work

poem and literary work both are nouns.

Word	Noun	Adjective	Verb	Adverb
poem	Yes	No	No	No
literary work	Yes	No	No	No

As nouns, literary work is a hypernym of poem; that is, literary work is a word with a broader meaning than poem:

Other hypernyms of poem include literary composition.

poem (noun)	literary work (noun)
a composition written in metrical feet forming rhythmical lines	imaginative or creative writing