Perhaps you should try some spelling variations:
formen lam » formen im, formen a, formen ab
formen das » formen des, fordern das, formen der
zwang iii » zugang iii
klang iii » klang die
david ng » david g, david n, david a
ng hai » dang hai, hong hai
qian » ian, kian, jian

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: qian rong ((zwang iii) OR (klang iii)) ((formen lam) OR (formen das)) david ng hai ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "qian rong ((zwang iii) OR (klang iii)) ((formen lam) or (formen das)) david ng hai ;~".
• Adding a wildcard symbol may retrieve word variants: qian rong ((zwang iii) OR (klang iii)) ((formen lam) or (formen das)) david ng hai ;*.