Perhaps you should try some spelling variations:
chiet tach » chieu sach
hanh trang » thanh trung, hanh trinh, minh trang
dung cong » dung trong
ho chiet » ho chieu, ho thiet, hoc thiet
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho chiet tach - ((hanh trang) OR (canh tranh)) su dung cong tac toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chiet tach - ((hanh trang) OR (canh tranh)) su dung cong tac toan cau".
• Adding a wildcard symbol may retrieve word variants: ho chiet tach - ((hanh trang) OR (canh tranh)) su dung cong tac toan cau*.