Perhaps you should try some spelling variations:
using lean » using less, using linear
wang kong » wang yong, wang hong, hong kong
kong heng » kong hang, kong hong, dong sheng
sind lean » sind ein
der rent » der re
der rede » der redner, der re
how slow » how low, how slower, grow slow

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: wang kong heng ((der rent) OR (der rede)) ((using lean) OR (sind lean)) how slow ;~.
• Adding a wildcard symbol may retrieve word variants: wang kong heng ((der rent) or (der rede)) ((using lean) or (sind lean)) how slow ;*.