Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
hieu manh » chieu xanh, hieu nganh, dieu hanh
trinh qua » trinh quan, trinh cua, trinh quang
hoc hieu » hoc thieu, hoc hien, doc hieu
qua dung » quang dung, su dung, qua song
than cao » toan cao, thai cao, than cap
cong tu » cong cu, dong tu, cong ti

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 manh - canh trinh qua dung ((cong tu) or (cong ty)) than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - canh trinh qua dung ((cong tu) OR (cong ty)) than cao.
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - canh trinh qua dung ((cong tu) or (cong ty)) than cao*.