How can I find the tracking number of the US Postal service carrier my package was transferred to?

China Post tracking AM246990939CN

Hi, I have sent a very important document from Australia to China (EJ308962541AU), from China EMS system, it showed it is still not arrived in China, however from AU POST website, it is clearly stated that is was Ready for postal carrier to collect, I have called several times to China EMS and Aus post, no more update, now it is over a month since I sent it on 12nd May, would it get lost? thanks.

Me Again :-) so my package was handed over to a carrier whether that be a truck or van courier 7 days ago , your postal system is really confusing cause on the 13th nov it was ready to be shipped in transit to NZ But now its bouncing around china again? so could you please tell me where the carrier will go with it , to the international airport? to another carrier? also can you tell me what does E-packet mean .. and what is the code for a HEAVYWEIGHT package as my package is supposed to be Heavy . thankyou have a great day