Perhaps you should try some spelling variations:
cong nguong » cong nguon, cong thuong, cong luong
quang cong » quang cuong, quang dong, quang hoang
nguong dan » huong dan
hien xanh » hien hanh, hien nhanh, chieu xanh
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
phan cau » phan cac, phan tu, phan lap
phan dau » phan tu, hang dau

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 - hanh tinh quang cong nguong dan ((phan cau) OR (phan dau))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien xanh - hanh tinh quang cong nguong dan ((phan cau) OR (phan dau))".
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - hanh tinh quang cong nguong dan ((phan cau) OR (phan dau))*.