Perhaps you should try some spelling variations:
thiet hach » thien hach, thuyet hach, thiet hai
hanh trinh » canh tranh, hanh chinh
quan hoang » luan hoan
quan hang » quan lang, quan hanh, qua hang
ho thiet » hoc thiet, hoa thiet, so thiet
cong tan » cong tac, cong san, cong thanh
tan van » tran van, tang van, luan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho thiet hach - hanh trinh ((quan hang) or (quan hoang)) cong tan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho thiet hach - hanh trinh ((quan hang) OR (quan hoang)) cong tan van ban.
• Adding a wildcard symbol may retrieve word variants: ho thiet hach - hanh trinh ((quan hang) or (quan hoang)) cong tan van ban*.