Perhaps you should try some spelling variations:
chieu sach » chinh sach, chieu sang, chieu xanh
hanh trinh » canh tranh, hanh chinh
hieu manh » chieu xanh, hieu nganh, dieu hanh
trinh va » trinh van, trinh vat, trinh ve
dung ung » dung cong
dan toan » van toan, dan than, manh toan
toan cau » toan cao, toan ban, toan tap
va dung » van dung, va duong, vat dung
ung dan » dung dan, tung dan, bung dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((hieu manh) or (((chieu sach) OR (chiet tach)))) - hanh trinh va dung ung dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu manh) OR (((chieu sach) OR (chiet tach)))) - hanh trinh va dung ung dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu manh) or (((chieu sach) OR (chiet tach)))) - hanh trinh va dung ung dan toan cau".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu manh) or (((chieu sach) OR (chiet tach)))) - hanh trinh va dung ung dan toan cau*.