Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
nang ma » sang ma, nang cao, mang may
tang ma » mang may, tang van
dai tac » dai tai, doi tac, da tac
va hanh » van hanh, va thanh, va danh
tac va » tac da, tac xa, tuc va
vi cua » vai cua, di cua

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: su sach ty ((nang ma) OR (tang ma)) hoi. hieu hien dai tac va hanh vi cua vat~.
• Adding a wildcard symbol may retrieve word variants: su sach ty ((nang ma) or (tang ma)) hoi. hieu hien dai tac va hanh vi cua vat*.