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 » truong thanh
gain china » spain china, can china, dan china
long thanh » long han, long trinh, truong thanh
ahp using » top using, up using
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 (long thanh)) ;~.
• Adding a wildcard symbol may retrieve word variants: land planning gain china ((ip using) or (ahp using)) tik ((luong thanh) or (long thanh)) ;*.