Perhaps you should try some spelling variations:
land planning » based planning, road planning
dam planning » term planning, from planning, 2 planning
congo mali » congo call
china tan » china top, china two, china taiwan
cong van » congo can, duong van, cong sun
tan anh » tuan anh, tan ah, dang anh

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: ((dam planning) OR (land planning)) can china tan anh minh ((congo mali) OR (cong van)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((dam planning) OR (land planning)) can china tan anh minh ((congo mali) or (cong van)) ;~".
• Adding a wildcard symbol may retrieve word variants: ((dam planning) OR (land planning)) can china tan anh minh ((congo mali) or (cong van)) ;*.