i think bitcoin are out control of government so that if china ban bitcoin it is not important things
Not completely true. BTC is indeed out of government control ( can't "manipulate" it directly ) ... but is proven that major bans and restrictions seriously affects the BTC price ... which is quite important thing.
Yes bitcoin can't be controlled but bitcoin exchanges can be and that's what it is being said and heard what China has decided to do and because of that bitcoin prices seem to have fallen to such low but I am pretty sure that the effect of China banning, regulating bitcoin exchanges etc on bitcoin prices is short lived and bitcoin will register an ATH soon