Your sentence is correct but awkward. I think it should be "need to": - Nobody needs to know everything, but everybody needs to want to know everything. The 2nd clause is still awkward, though: - Nobody needs to know everything, but they should /want/ to know everything. (In speech, you'd stress the word "want", in writing you'd italicize it for emphasis.) I think (but could be wrong) there is a similar, slight difference between Spanish "tener/hay que" and "necesitar": - tengo que hacerlo => I must do it - necesito que hacerlo => I need to do it

Nobody has to know everything, but everyone must want to know everything.?