Perhaps you should try some spelling variations:
thieu tinh » chieu tinh, thien tinh, lieu tinh
canh trang » canh tranh, hanh trang, banh trang
dung cong » dung trong
trang va » tran van, hang va
cong tan » cong tac, cong san, cong thanh
phan dau » phan tu
hang dau » hang va, hang tai
va dung » van dung, va duong, vat dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu tinh) or (trieu tinh)) - canh trang va dung cong tan ((phan dau) OR (hang dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu tinh) OR (trieu tinh)) - canh trang va dung cong tan ((phan dau) OR (hang dau))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu tinh) or (trieu tinh)) - canh trang va dung cong tan ((phan dau) OR (hang dau))*".