When you open a file directly from Adobe Reader, you should be prompted to download a font package (see screenshot below). Please follow the link from your browser and install the package as per the instructions. You will only need to this once and you will then be able to see all PDFs with Chinese characters.
If your browser does not start, please follow the link below. Download and install the font pack. Again, you will only need to do this once.
https://supportdownloads.adobe.com/thankyou.jsp?ftpID=6839&fileID=6837