Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hanh tranh » canh tranh, hanh trang, lanh tranh
hieu cach » hieu cac, chieu sach, hieu ca
cua nhung » va nhung
duong van » duong va, luong va, dang van
hoc hieu » hoc thieu, hoc hien, doc hieu
song van » hoang van, trong van, dang van
tuan cau » toan cau, quan cau, tuan cu

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 cach - ((hanh tranh) or (hanh trinh)) cua nhung ((song van) OR (duong van)) tuan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu cach - ((hanh tranh) OR (hanh trinh)) cua nhung ((song van) OR (duong van)) tuan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu cach - ((hanh tranh) or (hanh trinh)) cua nhung ((song van) OR (duong van)) tuan cau".
• Adding a wildcard symbol may retrieve word variants: hoc hieu cach - ((hanh tranh) or (hanh trinh)) cua nhung ((song van) OR (duong van)) tuan cau*.