Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hieu lang » chieu sang, nhieu tang, hieu van
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
cua thong » cua thuong, cua khong, cua tong
cong danh » cuong danh, cong thanh, cong khanh
tinh cua » trinh cua, sinh cua, tinh chat
cong dan » cong san, cong tan, huong dan
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: ho ((hieu lang) or (hieu quang)) - hanh tinh cua thong ((cong danh) OR (cong dan)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu lang) OR (hieu quang)) - hanh tinh cua thong ((cong danh) OR (cong dan)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu lang) or (hieu quang)) - hanh tinh cua thong ((cong danh) OR (cong dan)) toan cau".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu lang) or (hieu quang)) - hanh tinh cua thong ((cong danh) OR (cong dan)) toan cau*.