Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hanh tai » thanh tai, hang tai, han tai
hanh dai » hanh dao, vanh dai, thanh dat
cao duc » dao duc, cao suc, giao duc
thu san » thuy san, thu ban, phu san
cai duc » mai duc, hoai duc, chi duoc
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
san ky » sang ky, van ky, dan ky

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu san ky lang xa hoi. hieu qua ((cai duc) OR (cao duc)) tan ((hanh dai) or (hanh tai)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu san ky lang xa hoi. hieu qua ((cai duc) OR (cao duc)) tan ((hanh dai) OR (hanh tai)) cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu san ky lang xa hoi. hieu qua ((cai duc) OR (cao duc)) tan ((hanh dai) or (hanh tai)) cua viet".
• Adding a wildcard symbol may retrieve word variants: thu san ky lang xa hoi. hieu qua ((cai duc) OR (cao duc)) tan ((hanh dai) or (hanh tai)) cua viet*.