Perhaps you should try some spelling variations:
thieu bien » thieu nien, tieu bieu, hien bien
cua viet » ca viet, cua vat, cua dieu
cac truc » cau truc, cac tru, cac trung
bien cac » vien cac, dien cac, bien ca
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
tu sach » thu sach, su sach, te sach
sach tu » sach thu, cach tu, sach ty
nang xa » lang xa, nang ma, mang xa

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 sach tu ((nang xa) OR (nang x)) hoi. thieu bien cac truc va hanh vi ((cua viet) OR (hoa viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tu ((nang xa) or (nang x)) hoi. thieu bien cac truc va hanh vi ((cua viet) OR (hoa viet))~".
• Adding a wildcard symbol may retrieve word variants: tu sach tu ((nang xa) or (nang x)) hoi. thieu bien cac truc va hanh vi ((cua viet) OR (hoa viet))*.