Perhaps you should try some spelling variations:
hieu xanh » chieu xanh, hieu manh, hieu nganh
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
cong lang » cong vang, cong luong, cong quang
doc hieu » toc thieu, hoc thieu, hoc hien
cua dong » chua dong, cua dang, cua nong
than cau » toan cau, phan cau, thanh chau
than cap » khan cap, thanh lap, thanh cac

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 xanh - hanh tinh ((cua dong) or (cua cong)) cong lang ((than cau) OR (than cap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - hanh tinh ((cua dong) OR (cua cong)) cong lang ((than cau) OR (than cap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - hanh tinh ((cua dong) or (cua cong)) cong lang ((than cau) OR (than cap))".
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - hanh tinh ((cua dong) or (cua cong)) cong lang ((than cau) OR (than cap))*.