breadstick vs breadstuff

breadstick and breadstuff both are nouns.

Word	Noun	Adjective	Verb	Adverb
breadstick	Yes	No	No	No
breadstuff	Yes	No	No	No

As nouns, breadstuff is a hypernym of breadstick; that is, breadstuff is a word with a broader meaning than breadstick:

breadstick: a crisp stick-shaped roll; often served with soup
breadstuff: food made from dough of flour or meal and usually raised with yeast or baking powder and then baked

Other hypernyms of breadstick include bread, staff of life.

breadstick (noun)	breadstuff (noun)
a crisp stick-shaped roll; often served with soup	food made from dough of flour or meal and usually raised with yeast or baking powder and then baked
	flour or meal or grain used in baking bread