Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hieu lang » chieu sang, hieu quang, nhieu tang
hanh tang » hanh trang, anh tang, hanh mang
cua thong » cua thuong, cua khong, cua tong
tang cua » mang cua, hang cua, tang luan
tien van » thien van, trien van, tien va
tin van » tan van, tin va, tin vao

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu lang) or (chieu sach)) - hanh tang cua thong thong ((tin van) OR (tien van)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu lang) OR (chieu sach)) - hanh tang cua thong thong ((tin van) OR (tien van)) ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu lang) or (chieu sach)) - hanh tang cua thong thong ((tin van) OR (tien van)) ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu lang) or (chieu sach)) - hanh tang cua thong thong ((tin van) OR (tien van)) ban*.