Since a couple years ago, mainland China has ramped up its scheme for tax refunds on purchases at certain large stores. The number of stores doing such service has really increased which is a nice thing.

Just an advice : if your exit from mainland China involves a domestic correspondance before exiting the territory, you have to get the customs stamp and obtain the refund at your final mainland airport. This is similar to the European Union, but involves some planning of the transfering time. If your items are in your checked luggage, you have to reclaim it at your transfer port, go landside to show the items and get the customs stamp, before re-checking the bags and going through the contrôle security all over again. This holds true if you have your goods in your carry-on, less the reclaiming/rechecking bagages- but you still have to go landside.

In my case (SZX - PVG - FRA) , the check in agent could then only check me in/give me the boarding card for the domestic segment, because the checked bags would only be tagged to PVG. A delay on the inbound meant my 3h correspondance at PVG shrank to 2h, which was a bit tight. Luckily priority bagage delivery and recheck (and super-fast luggage delivery) and no queues meant things ended well. But I could see things going awry if not careful.

So plan your transferring accordingly.