Capul ce se pleaca
Sabia nu-l taie.

There are two more lines, which make the point of the proverb:
Dar cu umilinta
Ea il inconvoaie.
(But it is covered in humiliation.)

Sword don't cut the bowed head

I'm sorry that you think this saying speaks about the Romanian state of mind, especially without considering also the second part of it, "Capul ce se pleaca sabia nu-l taie, dar cu umilinta ea il inconvoaie" (The head that bows is not cut off, but is covered with humiliation). [This is from a poem written by a Romanian poet, Bolintineanu I guess, but there is another form, more popular, for it: "Capul plecat sabia nu-l taie, dar nici soarele nu vede" (The head that bows is not cut off, but it does not see the sun either)] I admit that it has been used intensively with the meaning given by its truncated version, but at least let us not perpetuate this idea; this is not an original thought of the Romanian people, but is reflection into the conscience of some Romanians who think that a cynical resignation is the only stance to be taken against the hardships of life.

It's the literary translation of this Romanian expression. To my knowledge, there is no English equivalent to it.

The other two lines should be:

But will bend with humility to it

(The real meaning is:
He who obeys will not perish by the sword
but will be humiliated and dishonored)

An alternative translation.
A slight modification, still yet correct, would also be to change “A” with “The” (The bowed head...).