Perhaps you should try some spelling variations:
theo chieu » theo tieu, ho chieu, theo chu
hanh trinh » canh tranh, hanh chinh
hoc thiet » hoc thieu, hoc thuyet, hoc hien
trinh hai » trinh khai, trinh han, trinh tai
san thong » san thuong, sau thong, san khong
ban thong » ban trong, ban tuong, ban tong
dan than » dan chan, ban than, van than
than cao » toan cao, thai cao, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc thiet) or (theo chieu)) tach - hanh trinh hai ((san thong) OR (ban thong)) dan than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thiet) OR (theo chieu)) tach - hanh trinh hai ((san thong) OR (ban thong)) dan than cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thiet) or (theo chieu)) tach - hanh trinh hai ((san thong) OR (ban thong)) dan than cao".
• Adding a wildcard symbol may retrieve word variants: ((hoc thiet) or (theo chieu)) tach - hanh trinh hai ((san thong) OR (ban thong)) dan than cao*.