Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hanh trinh » canh tranh, hanh chinh
dang huong » dang thuong, dang hung, dong huong
trinh vat » trinh van, trinh luat, sinh vat
thanh cac » hanh cac, thanh bac, thanh ca
hop hieu » hop nhieu, hoi hieu, hoc thieu
vat dang » van dang, vat dung, va dang
phan cau » phan dau, phan cac, phan tu
than cap » khan cap, thanh lap, than cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: hop hieu quang - hanh trinh vat dang huong dan ((phan cau) or (((than cap) or (thanh cac))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hop hieu quang - hanh trinh vat dang huong dan ((phan cau) OR (((than cap) OR (thanh cac)))).
• Adding a wildcard symbol may retrieve word variants: hop hieu quang - hanh trinh vat dang huong dan ((phan cau) or (((than cap) or (thanh cac))))*.