I have a return flight from Bangkok to Shanghai for under 72 hrs. Can i get a visa for this

Graeme, do you intend to make use of the 72h free transit? If you fly from Shanghai to a third country or region, you qualify for the free transit and the entry permit is not necessary.

HI Sophie. Thanks for your reply. So i do need to fly to a third country? Will this work.. If I kept my return flight from bangkok to shanghai, and also bought a one way to a third country (siem reap) for the purpose of showing them a third country, and threw that ticket away soon after. Will this allow me to get a transit visa?

Why do you throw the ticket away? May I know your planned route? I'm confused.