Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh gian » trinh giang, trinh giao, trinh giai
doi chieu » doc hieu, doi chi, ho chieu
hoc thieu » toc thieu, hoc hien
lang cong » bang cong, hang cong, lang dong
dang cong » dung cong
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: ((doi chieu) or (hoc thieu)) xanh - hanh trinh gian ((lang cong) OR (dang cong)) tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (hoc thieu)) xanh - hanh trinh gian ((lang cong) OR (dang cong)) tac toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) or (hoc thieu)) xanh - hanh trinh gian ((lang cong) OR (dang cong)) tac toan cau".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (hoc thieu)) xanh - hanh trinh gian ((lang cong) OR (dang cong)) tac toan cau*.