Translation:The humanity helps humans live well.
DL insists on "the humanity" but "the humanity" is not what we say in English. "Humanity" is correct.
I've never seen "the humanity" used this way before. This sentence makes no sense to me. Maybe "compassion" would be a better translation than "humanity."
definitely not the correct English translation! One would never say it like that.
in the other sentence, it had to be gíup đở, so there is some inconsistency here.
Giúp đở is used when you help some else, hence there's "Tự giúp mình đi" (help yourself), but "tự giúp đở mình đi" sounds pretty odd.
What is the meaning of "humanity" here?
In English, the most common usage would be as a noun, as a synonym for "humankind", but in this sentence the inferred meaning seems to be "treating people decently", or "treating people with consideration and kindness", etc. I say this as I would guess using "tính nhân đạo' as 'humankind' would be marked wrong in another usage.