Want to marry a chinese girl??

I am a Pakistani,wants to marry a chinese girl,i read that i need a attested non-marriage certificate to show the chinese governmment that i am unmarried yet,how can i get that?
Because i am not going back to Pak now so how can i get that certificate?is there any other way?
And what else documents i need?
I am in a hurry so will be waiting for the reply impatiently.