Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hieu lang » chieu sang, hieu quang, nhieu tang
hanh hang » thanh hang, hang hang, hanh han
cua thong » cua thuong, cua tong, suat thong
cua khong » hua khong, cua phuong, cua thuong
thong tan » thong than, thong tran, thong tin
tan toan » tan tran, tap toan, van toan
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((chieu sach) or (hieu lang)) - hanh hang ((cua thong) OR (cua khong)) thong tan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu sach) OR (hieu lang)) - hanh hang ((cua thong) OR (cua khong)) thong tan toan cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sach) or (hieu lang)) - hanh hang ((cua thong) OR (cua khong)) thong tan toan cau*".