Perhaps you should try some spelling variations:
trien quang » tran quang, tuyen quang, dien quang
thieu sang » chieu sang, thieu khang, thieu quang
hanh trang » thanh trung, canh tranh, hanh trinh
nhung cong » dung cong, thong cong, hang cong
trang cua » tranh cua, tang cua, trung cua
cua nhung » va nhung
dan toan » dan than, manh toan, xuan toan
van toan » van tuan, van tan, van thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu sang) or (trien quang)) - hanh trang cua nhung cong ((dan toan) OR (van toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (trien quang)) - hanh trang cua nhung cong ((dan toan) OR (van toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) or (trien quang)) - hanh trang cua nhung cong ((dan toan) OR (van toan)) cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) or (trien quang)) - hanh trang cua nhung cong ((dan toan) OR (van toan)) cao*.