Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, truong thanh
hieu xanh » chieu xanh, hieu manh, hieu nganh
hanh phan » thanh phan, anh phan, hanh han
doc hieu » toc thieu, hoc thieu, hoc hien
phan cua » nhan cua, than cua, phat cua
cua tong » cua cong, cua dong, cua nong
cong tan » cong tac, cong san, cong ty
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: doc hieu xanh - hanh phan cua tong ((cong tan) or (cong thanh)) ((toan cau) or (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - hanh phan cua tong ((cong tan) OR (cong thanh)) ((toan cau) OR (toan ban)).
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - hanh phan cua tong ((cong tan) or (cong thanh)) ((toan cau) or (toan ban))*.