Perhaps you should try some spelling variations:
thieu quang » hieu quang, thien quan, trien quang
thanh trang » thanh trung, thanh thang, thanh tran
hanh trang » thanh trung, canh tranh, hanh trinh
hoc thieu » toc thieu, hoc hien
tac toan » tap toan, tam toan, hach toan
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 quang - ((thanh trang) or (hanh trang)) va ((dung cong) OR (dung trong)) tac toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu quang - ((thanh trang) OR (hanh trang)) va ((dung cong) OR (dung trong)) tac toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu quang - ((thanh trang) or (hanh trang)) va ((dung cong) OR (dung trong)) tac toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc thieu quang - ((thanh trang) or (hanh trang)) va ((dung cong) OR (dung trong)) tac toan cao*.