successfulness vs good luck

successfulness and good luck both are nouns.

Word	Noun	Adjective	Verb	Adverb
successfulness	Yes	No	No	No
good luck	Yes	No	No	No

As nouns, good luck is a hypernym of successfulness; that is, good luck is a word with a broader meaning than successfulness:

Other hypernyms of successfulness include good fortune, luckiness.

successfulness (noun)	good luck (noun)
the condition of prospering; having good fortune	an unexpected piece of good luck
	a stroke of luck
	an auspicious state resulting from favorable outcomes