Perhaps you should try some spelling variations:
hanh trinh » canh tranh
cong ngang » cong nhan, cong quang, cong nong
hieu lang » chieu sang, hieu quang, nhieu tang
quan dung » quang dung, quan duong, qua dung
cong lang » cong vang, cong luong, cong quang
toan cau » toan cao, toan ban, toan tap
ho hieu » ho chieu, hoi hieu, nho hieu

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 - ((hanh trinh) or (hanh chinh)) quan dung ((cong ngang) OR (cong lang)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - ((hanh trinh) OR (hanh chinh)) quan dung ((cong ngang) OR (cong lang)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu lang - ((hanh trinh) or (hanh chinh)) quan dung ((cong ngang) OR (cong lang)) toan cau".
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - ((hanh trinh) or (hanh chinh)) quan dung ((cong ngang) OR (cong lang)) toan cau*.