Perhaps you should try some spelling variations:
referaten von » referat von, referat vom, reformen von
liang wei » xiang wei, zhang wei, fang wei
von david » john david, ben david, jan david
wan wang » wen wang, yan wang, wang yang
wang wei » zhang wei, wang zhi
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.

• Performing a fuzzy search may retrieve terms with similar spellings: wan wang ((liang wei) OR (wang wei)) referaten von david ng tan ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wan wang ((liang wei) OR (wang wei)) referaten von david ng tan ;*".