Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hanh trinh » canh tranh, hanh chinh
luan chung » luan chinh
hieu lang » chieu sang, nhieu tang, hieu van
cua nhung » va nhung
cong tinh » cong trinh, cong vinh, long tinh
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: ho ((hieu lang) OR (hieu quang)) - hanh trinh ((luan chung) or (cua nhung)) cong tinh toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu lang) OR (hieu quang)) - hanh trinh ((luan chung) OR (cua nhung)) cong tinh toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu lang) OR (hieu quang)) - hanh trinh ((luan chung) or (cua nhung)) cong tinh toan ban".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu lang) OR (hieu quang)) - hanh trinh ((luan chung) or (cua nhung)) cong tinh toan ban*.