Perhaps you should try some spelling variations:
thieu cach » hieu cach, thieu cac, hieu cac
phung cong » nhung cong, phong cong, nhung chong
hoc thieu » toc thieu, hoc hien
canh tinh » hanh tinh, canh tranh, nhanh tinh
manh tinh » man tinh, manh binh, hanh tinh
hung cong » nhung cong, hung cuong, dung cong
dan than » dan chan, ban than, van than
than tap » toan tap, han tap, phan tap

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 cach - ((canh tinh) OR (manh tinh)) luan ((hung cong) or (phung cong)) dan than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu cach - ((canh tinh) OR (manh tinh)) luan ((hung cong) OR (phung cong)) dan than tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu cach - ((canh tinh) OR (manh tinh)) luan ((hung cong) or (phung cong)) dan than tap".
• Adding a wildcard symbol may retrieve word variants: hoc thieu cach - ((canh tinh) OR (manh tinh)) luan ((hung cong) or (phung cong)) dan than tap*.