Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
thu canh » thuc hanh, thu cong, thu ban
tan hanh » tan thanh, tang hanh, toan hanh
hanh de » hanh ve, hanh kem
cac duc » cao duc, cac dac, cac nuoc
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
de cua » le cua, te cua, dieu cua
tu can » tu ban, tu cac

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

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