Perhaps you should try some spelling variations:
thieu sang » thieu khang, thieu quang, hieu lang
chieu sang » chieu sach, chieu xanh, hieu lang
nhung cong » thong cong, hang cong, nhung don
hanh tang » hanh trang, anh tang, hanh mang
dung cong » dung trong
manh toan » thanh toan, anh tuan, tinh toan
tang cua » mang cua, hang cua, tang luan
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: hoc ((thieu sang) OR (chieu sang)) - hanh tang cua ((nhung cong) or (dung cong)) manh toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (chieu sang)) - hanh tang cua ((nhung cong) OR (dung cong)) manh toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (chieu sang)) - hanh tang cua ((nhung cong) or (dung cong)) manh toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (chieu sang)) - hanh tang cua ((nhung cong) or (dung cong)) manh toan cau*.