Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hieu manh » chieu xanh, hieu nganh, dieu hanh
hieu lang » chieu sang, nhieu tang, hieu van
bang cong » dang cong, bang song, hang cong
hang ban » hang luan, hang va, hang tai
cua bang » chua bang, cua ban, cua dang
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than ban » thanh ban, toan ban, than man
ban cua » ban quan

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu manh) OR (((hieu lang) OR (hieu quang)))) - hang ban cua bang cong dan than ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu manh) or (((hieu lang) OR (hieu quang)))) - hang ban cua bang cong dan than ban~".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu manh) or (((hieu lang) OR (hieu quang)))) - hang ban cua bang cong dan than ban*.