If you only apply for a design, you can't be granted a patent right.
You can apply for wallpaper and patent for "design" with this pattern. Wallpaper is a flat product and can be patented.
If you have time, I suggest you go to official website, China National Intellectual Property Administration to search for "wallpaper" or "wallpaper" related patent authorization public text. It may help you to apply for a patent.
If you are not very short of funds, I suggest that you entrust a formal patent agency to handle patent application related matters, so as to ensure authorization.
Good luck with your patent application.