Perhaps you should try some spelling variations:
chiet tach » chieu sach
hanh trinh » canh tranh, hanh chinh
hien tach » thien hach, vien bach, hien hanh
trong dan » trong dang, trong san, trong tan
trinh va » trinh van, trinh vat, trinh ve
dan toan » van toan, dan than, manh toan
toan cau » toan cao, toan ban, toan tap
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 ((hien tach) or (chiet tach)) - hanh trinh va dung trong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien tach) OR (chiet tach)) - hanh trinh va dung trong dan toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((hien tach) or (chiet tach)) - hanh trinh va dung trong dan toan cau*.