Perhaps you should try some spelling variations:
khong cong » thong cong, khong cang, chong cong
chieu xanh » chieu sach, chieu sang, chieu tinh
hien xanh » hien hanh, hien nhanh, hien khanh
hanh tang » hanh trang, anh tang, hanh mang
cua khong » hua khong, cua phuong, cua thuong
tang cua » mang cua, hang cua, tang luan
dan than » dan chan, ban than, van than
dan han » dan chan, dan hanh, dan phan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hien xanh) or (chieu xanh)) - hanh tang cua khong cong ((dan han) OR (dan than)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien xanh) OR (chieu xanh)) - hanh tang cua khong cong ((dan han) OR (dan than)) tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien xanh) or (chieu xanh)) - hanh tang cua khong cong ((dan han) OR (dan than)) tap".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) or (chieu xanh)) - hanh tang cua khong cong ((dan han) OR (dan than)) tap*.