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