Perhaps you should try some spelling variations:
land planning » based planning, road planning, dam planning
planning gain » planning chain, planning against, planning guide
luong thanh » long thanh, truong thanh
gain china » spain china, can china, dan china
ahp using » top using, up using
hong than » hong tan, long thanh, hong hai
ip using » up using, top using, 4 using

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: land planning gain china ((ip using) OR (ahp using)) tik ((luong thanh) OR (hong than)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "land planning gain china ((ip using) OR (ahp using)) tik ((luong thanh) or (hong than)) ;~".
• Adding a wildcard symbol may retrieve word variants: land planning gain china ((ip using) OR (ahp using)) tik ((luong thanh) or (hong than)) ;*.