Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hieu manh » chieu xanh, hieu nganh, dieu hanh
quang cao » nang cao, quang nam
hoc hieu » hoc thieu, hoc hien, doc hieu
cua rung » cua trung, cua rang, cua truong
qua dung » quang dung, su dung, qua song
cong anh » cong danh, dong anh, hong anh
quan cau » toan cau, quan ha, quan cua

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