Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
mai viet » thi viet
vien dai » hien dai
thu sach » thuat sach, thuoc sach, thu hoach
hanh vai » hanh vi, hanh va, hanh tai
ca viet » va viet, co viet, hoa viet
va hanh » van hanh, va thanh, va danh
tu sach » su sach, te sach, tu cach
xang xa » lang xa, mang xa, ang xa
dai xuc » dai xu, dai luoc, dai thuc
xuc va » duc va, tuc va, luc 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 sach) or (thu sach)) ty xang xa hoi. hieu vien dai xuc va hanh vai ((ca viet) or (mai viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ty xang xa hoi. hieu vien dai xuc va hanh vai ((ca viet) OR (mai viet)).
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ty xang xa hoi. hieu vien dai xuc va hanh vai ((ca viet) or (mai viet))*.