Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
dung cong » dung trong
hoc dien » hoc dieu, hoc lien, hoc tien
hoc vien » hoc viet, hoc tieng, hoc vi
trinh va » trinh van, trinh vat, trinh ve
cong tan » cong tac, cong san, cong thanh
va dung » van dung, va duong, vat dung
tan van » tran van, tang van, luan van
van dau » van dao, phan dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((((hoc dien) or (hoc vien))) or (hoc hien)) anh - canh trinh va dung cong tan van dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((hoc dien) OR (hoc vien))) OR (hoc hien)) anh - canh trinh va dung cong tan van dau.
• Adding a wildcard symbol may retrieve word variants: ((((hoc dien) or (hoc vien))) or (hoc hien)) anh - canh trinh va dung cong tan van dau*.