Perhaps you should try some spelling variations:
chieu tinh » trieu tinh, lieu tinh, chau tinh
nhung cong » thong cong, hang cong, nhung don
hoc chieu » hoc thieu, ho chieu, hoc hien
tranh cua » doanh cua, manh cua
dung cong » dung trong
toan cao » toan tap
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc chieu tinh - canh tranh cua ((nhung cong) or (dung cong)) dan ((toan cao) OR (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chieu tinh - canh tranh cua ((nhung cong) OR (dung cong)) dan ((toan cao) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chieu tinh - canh tranh cua ((nhung cong) or (dung cong)) dan ((toan cao) OR (toan ban))".
• Adding a wildcard symbol may retrieve word variants: hoc chieu tinh - canh tranh cua ((nhung cong) or (dung cong)) dan ((toan cao) OR (toan ban))*.