Perhaps you should try some spelling variations:
phuong cong » phuong dong, phong cong, phung cong
hieu lang » chieu sang, hieu quang, nhieu tang
tang xuan » tang quan, dang xuan, lang xuan
tang luan » dung luan
doi hieu » doi chieu, doc hieu, doi hien
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: doi hieu lang - anh ((tang xuan) OR (tang luan)) phuong cong dan ((toan cau) or (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - anh ((tang xuan) OR (tang luan)) phuong cong dan ((toan cau) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi hieu lang - anh ((tang xuan) OR (tang luan)) phuong cong dan ((toan cau) or (toan ban))".
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - anh ((tang xuan) OR (tang luan)) phuong cong dan ((toan cau) or (toan ban))*.