Perhaps you should try some spelling variations:
hien xanh » hien hanh, hien nhanh, chieu xanh
dung cong » dung trong
trung ha » trung hoc, trung tam, trung cap
trang va » tran van, hang va
cong dan » cong san, cong tan, huong dan
toan cau » toan cao, toan tap, toan tai
toan ban » van ban

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 ((trung ha) or (trang va)) dung cong dan ((toan cau) OR (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - hanh ((trung ha) OR (trang va)) dung cong dan ((toan cau) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien xanh - hanh ((trung ha) or (trang va)) dung cong dan ((toan cau) OR (toan ban))".
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - hanh ((trung ha) or (trang va)) dung cong dan ((toan cau) OR (toan ban))*.