Perhaps you should try some spelling variations:
hanh trinh » canh tranh
dung cong » dung trong
cong tang » cong thang, cong tan, cong lang
hoc dien » hoc vien, hoc dieu, hoc lien
vat dung » van dung, va dung, viet dung
tang van » dang van, hoang van, trong van
van cau » van dau, van hau, van chat

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 hien)) dan - ((hanh trinh) OR (hanh chinh)) vat dung cong tang van cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc dien) OR (hoc hien)) dan - ((hanh trinh) OR (hanh chinh)) vat dung cong tang van cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc dien) or (hoc hien)) dan - ((hanh trinh) OR (hanh chinh)) vat dung cong tang van cau".
• Adding a wildcard symbol may retrieve word variants: ((hoc dien) or (hoc hien)) dan - ((hanh trinh) OR (hanh chinh)) vat dung cong tang van cau*.