Perhaps you should try some spelling variations:
class dong » class doing, class do
dong since » dong sin
yang guang » yang yang, yan guan, yang liang
one class » one case
since ce » since c, since _, since eu
song min » song ming, gong min, jong min
yang jie » yang jin, yang di, yang jui
yang xi » yang di, yang yi, yang jui

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: one class dong since ce ((((song min) OR (yang guang))) OR (yang jie)) ((wang yan) OR (yang xi)) ;~.
• Adding a wildcard symbol may retrieve word variants: one class dong since ce ((((song min) or (yang guang))) or (yang jie)) ((wang yan) or (yang xi)) ;*.