Perhaps you should try some spelling variations:
hoc thieu » hoc hien
canh tran » canh tranh, hanh trang, banh trang
dang cong » dung cong
tran van » luan van
van dang » van dong, van dung, van nang
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) OR (toc thieu)) sang - canh tran van dang cong ((dan toan) or (van toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thieu) OR (toc thieu)) sang - canh tran van dang cong ((dan toan) OR (van toan)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thieu) OR (toc thieu)) sang - canh tran van dang cong ((dan toan) or (van toan)) cau".
• Adding a wildcard symbol may retrieve word variants: ((hoc thieu) OR (toc thieu)) sang - canh tran van dang cong ((dan toan) or (van toan)) cau*.