Perhaps you should try some spelling variations:
reformen von » formen von, referaten von, reformen der
wang xiang » wang liang, wang yang, wang jing
reform von » form von
xiang wei » liang wei, zhang wei, wang wei
wan wang » wen wang, yan wang, wang yang
david ng » david g, david n, david a
ng tan » hong tan, wing tan

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: wan wang xiang wei ((reformen von) OR (reform von)) david ng tan ;~.
• Adding a wildcard symbol may retrieve word variants: wan wang xiang wei ((reformen von) or (reform von)) david ng tan ;*.