Perhaps you should try some spelling variations:
hieu suat » hieu luat, hieu qua
hieu sau » hieu su, tieu su, hieu va
ky sang » ky nang, ky tang, duy sang
ky dang » ky nang, ky danh
lai hoi » dai hoi, lai hoa, lai roi
va hanh » van hanh, va thanh, va danh
vi cua » vai cua, di cua
tu san » thu san, tu ban, tu can
cua te » cua tu
xu va » xu van, tu va, su va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu san ((ky sang) or (ky dang)) lai hoi. ((hieu sau) OR (hieu suat)) chao xu va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ((ky sang) OR (ky dang)) lai hoi. ((hieu sau) OR (hieu suat)) chao xu va hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu san ((ky sang) or (ky dang)) lai hoi. ((hieu sau) OR (hieu suat)) chao xu va hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: tu san ((ky sang) or (ky dang)) lai hoi. ((hieu sau) OR (hieu suat)) chao xu va hanh vi cua te*.