Perhaps you should try some spelling variations:
hieu suat » hieu luat, hieu qua
hieu sau » hieu su, tieu su, hieu va
tu sang » thu sang, tu san, tu lang
va danh » va dinh, va dan, va hanh
ky mang » ke mang, ky dang, ky tang
lai hoi » dai hoi, lai hoa, lai roi
danh vi » hanh vi, dinh vi, danh di
vi cua » vai cua, di cua
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 sang ((ky mang) or (ky nang)) lai hoi. ((hieu sau) OR (hieu suat)) chao xu va danh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sang ((ky mang) OR (ky nang)) lai hoi. ((hieu sau) OR (hieu suat)) chao xu va danh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sang ((ky mang) or (ky nang)) lai hoi. ((hieu sau) OR (hieu suat)) chao xu va danh vi cua te".
• Adding a wildcard symbol may retrieve word variants: tu sang ((ky mang) or (ky nang)) lai hoi. ((hieu sau) OR (hieu suat)) chao xu va danh vi cua te*.