This is an example of something that always wants more. Alternate translation: "Greed has two daughters" (See: [[rc://en/ta/man/translate/figs-metaphor]])
This use of the numbers "three" and "four" together here is likely a poetic device. Alternate translation: "There are four things that are never satisfied, who never say, 'Enough'" (See: [[rc://en/ta/man/translate/writing-poetry]])