Perhaps you should try some spelling variations:
hieu suat » hieu luat, hieu qua
mang lai » mang luoi, dang loai, trang lai
mang lam » bang lam, mang mam, nang lam
chat duc » chat xuc, chat doc, chet duoc
hieu su » hieu sau, tieu su, hieu so
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
di cua » dai cua, doi cua, de cua
tu sai » tu bai, tu san, tu cai
sai ky » sac ky
cua te » cua tu

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

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