Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hieu xanh » chieu xanh, hieu nganh, dieu hanh
hieu manh » chieu xanh, hieu nganh, dieu hanh
nha thong » nhan thong, nhat thuong, nghe thong
ha thong » hoa thong, he thong, va thong
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh 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: doc ((hieu xanh) or (hieu manh)) - hanh trinh ((ha thong) OR (nha thong)) cong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu xanh) OR (hieu manh)) - hanh trinh ((ha thong) OR (nha thong)) cong dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu xanh) or (hieu manh)) - hanh trinh ((ha thong) OR (nha thong)) cong dan toan cau".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu xanh) or (hieu manh)) - hanh trinh ((ha thong) OR (nha thong)) cong dan toan cau*.