Perhaps you should try some spelling variations:
hanh trang » thanh trung, canh tranh, hanh trinh
luan trong » luat trong, luan tuong, luong trong
quan trong » gian trong
lieu tinh » diep tinh, bien tinh
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: theo ((lieu tinh) or (trieu tinh)) - hanh trang ((luan trong) OR (quan trong)) cong tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((lieu tinh) OR (trieu tinh)) - hanh trang ((luan trong) OR (quan trong)) cong tac toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((lieu tinh) or (trieu tinh)) - hanh trang ((luan trong) OR (quan trong)) cong tac toan cau".
• Adding a wildcard symbol may retrieve word variants: theo ((lieu tinh) or (trieu tinh)) - hanh trang ((luan trong) OR (quan trong)) cong tac toan cau*.