There is a similar question in FAQ for FontForge (https://fontforge.github.io/faq.html#mingliu) where it is described that kaiu.ttf (and probably mingliu.ttf) font does not store the correct outlines and its outlines need special treatment in order to be rendered correctly. The Chinese glyphs are rendered wrong in RadPdfViewer as well. However, Adobe Reader, FoxitReader and ChromeViewer render the glyphs correctly.