Perhaps you should try some spelling variations:
thieu bien » thieu nien, tieu bieu, hien bien
van hanh » van thanh, ban hanh, van anh
sach thu » sach thue, sach thieu, sach tham
cua viet » ca viet, hoa viet, cua vat
nang xa » lang xa, nang ma, mang xa
bien ca » bien cac, bien cua, bien va
va hanh » va thanh, va danh, ban hanh
tu sach » thu sach, su sach, te sach
ca tuc » cua tuc, va tuc
vi cua » vai cua, di cua

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 thu ((nang xa) or (nang x)) hoi. thieu bien ca tuc ((va hanh) or (van hanh)) vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thu ((nang xa) OR (nang x)) hoi. thieu bien ca tuc ((va hanh) OR (van hanh)) vi cua viet.
• Adding a wildcard symbol may retrieve word variants: tu sach thu ((nang xa) or (nang x)) hoi. thieu bien ca tuc ((va hanh) or (van hanh)) vi cua viet*.