Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hieu lang » chieu sang, hieu quang, nhieu tang
trinh cua » tinh cua, trinh luat, trinh quan
cua trong » cua truong, cua trung, qua trong
hoc hieu » hoc thieu, hoc hien, doc hieu
dong van » duong van, dong von, dong va
dang van » hoang van, hang va
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu lang - hanh trinh cua trong ((dong van) or (dang van)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - hanh trinh cua trong ((dong van) OR (dang van)) toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - hanh trinh cua trong ((dong van) or (dang van)) toan cau*.