Perhaps you should try some spelling variations:
thieu xanh » hieu manh, thien anh, thien danh
chieu xanh » chieu sach, chieu sang, chieu tinh
thong cong » trong cong, tong cong, thong thong
canh tinh » hanh tinh, canh tranh, nhanh tinh
manh tinh » man tinh, manh binh, hanh tinh
cong tan » cong tac, cong san, cong thanh
tran ban » tranh ban, tran van, toan ban

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (chieu xanh)) - ((canh tinh) OR (manh tinh)) toan thong cong tan tran ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu xanh) or (chieu xanh)) - ((canh tinh) OR (manh tinh)) toan thong cong tan tran ban~".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) or (chieu xanh)) - ((canh tinh) OR (manh tinh)) toan thong cong tan tran ban*.