ability vs know-how

ability and know-how both are nouns.

Word	Noun	Adjective	Verb	Adverb
ability	Yes	No	No	No
know-how	Yes	No	No	No

As nouns, know-how is a hyponym of ability; that is, know-how is a word with a more specific, narrower meaning than ability:

ability: possession of the qualities (especially mental qualities) required to do something or get something done
know-how: the (technical) knowledge and skill required to do something

ability (noun)	know-how (noun)
the quality of being able to perform; a quality that permits or facilitates achievement or accomplishment	the (technical) knowledge and skill required to do something
possession of the qualities (especially mental qualities) required to do something or get something done