Did they provide international tracking? Is there no movement on either side? Sometimes vendors only provide the Aus tracking details but not China.
I'd probably look into changing the route if that's in the vendor's control. From what I've read, getting through Vic / Qld is risky (some parcels manage to get through, but I think that's luck). If you can re-route via Sydney before getting to its final destination, that would increase your chances. If that's not in control and you have a mate in Sydney you can ship to, maybe get it sent there and then have them send it to you.
Another thing you can consider is pay for the Express shipping option (DHL, FedEx) if that's available to you.
I can only speak for Syd as that's where I am. I've had 2 orders get to me safely from China last week. One was standard post; the other was DHL.