Perhaps you should try some spelling variations:
hanh trang » thanh trung, canh tranh, hanh trinh
nhung cong » thong cong, hang cong, nhung don
hieu lang » chieu sang, hieu quang, nhieu tang
hanh tang » anh tang, hanh mang, hanh tung
dung cong » dung trong
hoc hieu » hoc thieu, hoc hien, doc hieu
tan toan » tan tran, tap toan, van toan
toan ban » van ban

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 lang - ((hanh tang) or (hanh trang)) cua ((nhung cong) OR (dung cong)) tan toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - ((hanh tang) OR (hanh trang)) cua ((nhung cong) OR (dung cong)) tan toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu lang - ((hanh tang) or (hanh trang)) cua ((nhung cong) OR (dung cong)) tan toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - ((hanh tang) or (hanh trang)) cua ((nhung cong) OR (dung cong)) tan toan ban*.