Perhaps you should try some spelling variations:
bien quang » dien quang, trien quang, lien quan
nhung cong » dung cong, thong cong, hang cong
hien xanh » hien hanh, hien nhanh, chieu xanh
tinh quan » tinh quang, trinh quan, tin quan
cong tan » cong tac, cong san, cong thanh
tran cau » tran chau, toan cau, ran cau

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 quan) or (bien quang)) nhung cong tan tran cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - hanh ((tinh quan) OR (bien quang)) nhung cong tan tran cau*.