nail down vs come through

nail down and come through both are verbs.

Word	Noun	Adjective	Verb	Adverb
nail down	No	No	Yes	No
come through	No	No	Yes	No

As verbs, come through is a hypernym of nail down; that is, come through is a word with a broader meaning than nail down:

Other hypernyms of nail down include bring home the bacon, deliver the goods, succeed, win.

nail down (verb)	come through (verb)
make final; put the last touches on; put into final form	penetrate
define clearly	succeed in reaching a real or abstract destination after overcoming problems
succeed in obtaining a position	attain success or reach a desired goal
	continue in existence after (an adversity, etc.)