Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hieu manh » chieu xanh, hieu nganh, dieu hanh
tang luan » dung luan
hoc hieu » hoc thieu, hoc hien, doc hieu
tang cua » mang cua, hang cua, thong cua
van toan » van tuan, van tan, van thanh
dan chan » dan gian, dan ca, van chat

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

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