Perhaps you should try some spelling variations:
hieu suat » hieu luat, hieu qua
va hanh » van hanh, va thanh, va danh
chao su » cao su, chao xu, achat su
sang ma » tang ma, nang ma, sang tao
hieu so » thieu so
vi cua » vai cua, di cua
bai ky » ban ky, bac ky, dai ky
ma hoi » mai hoi, xa hoi, ma hoa
sai ky » sac ky
cua te » cua tu
su va » su van, tu va

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((bai ky) OR (sai ky)) sang ma hoi. ((hieu suat) OR (hieu so)) chao su va hanh vi cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((bai ky) OR (sai ky)) sang ma hoi. ((hieu suat) or (hieu so)) chao su va hanh vi cua te~".
• Adding a wildcard symbol may retrieve word variants: tu ((bai ky) OR (sai ky)) sang ma hoi. ((hieu suat) or (hieu so)) chao su va hanh vi cua te*.