Perhaps you should try some spelling variations:
lanh tranh » canh tranh, lan tranh, hanh trinh
hieu cach » hieu cac, chieu sach, hieu ca
cua nhung » va nhung
chong van » thong van, phong van, chong va
doc hieu » toc thieu, hoc thieu, hoc hien
hong van » hoang van, thong van, phong van
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: doc hieu cach - ((lanh tranh) or (hanh chinh)) cua nhung ((chong van) OR (hong van)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu cach - ((lanh tranh) OR (hanh chinh)) cua nhung ((chong van) OR (hong van)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu cach - ((lanh tranh) or (hanh chinh)) cua nhung ((chong van) OR (hong van)) toan cao".
• Adding a wildcard symbol may retrieve word variants: doc hieu cach - ((lanh tranh) or (hanh chinh)) cua nhung ((chong van) OR (hong van)) toan cao*.