Perhaps you should try some spelling variations:
hieu xanh » chieu xanh, hieu manh, hieu nganh
nhan dang » nhan dan, phan dang, tran dang
dang cong » dung cong
doc hieu » toc thieu, hoc thieu, hoc hien
dang cua » dung cua, dong cua, mang cua
cua dang » cua cong, cua ban
cong dan » cong san, cong tan, huong dan

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 - nhan dang cua dang cong dan ((toan ban) or (van ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - nhan dang cua dang cong dan ((toan ban) OR (van ban)).
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - nhan dang cua dang cong dan ((toan ban) or (van ban))*.