Perhaps you should try some spelling variations:
hieu suat » hieu luat, hieu qua
dang lai » dang loai, dang hai, dung lai
hieu sau » hieu su, tieu su, hieu va
chao su » cao su, chao xu, achat su
ky dang » ky nang, ky danh
lai hoi » dai hoi, lai hoa, lai roi
va hanh » van hanh, va thanh, va danh
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
cua tu » cua tuc, cua su, cua cu
su va » su van, tu 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 sac ky dang lai hoi. ((hieu sau) OR (hieu suat)) chao su va hanh vi ((cua te) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky dang lai hoi. ((hieu sau) OR (hieu suat)) chao su va hanh vi ((cua te) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky dang lai hoi. ((hieu sau) OR (hieu suat)) chao su va hanh vi ((cua te) or (cua tu))".
• Adding a wildcard symbol may retrieve word variants: tu sac ky dang lai hoi. ((hieu sau) OR (hieu suat)) chao su va hanh vi ((cua te) or (cua tu))*.