Perhaps you should try some spelling variations:
thiet hach » thien hach, thuyet hach, thiet hai
hanh trinh » canh tranh, hanh chinh
trinh quan » tinh quang, trinh luat, trinh han
nhung cong » dung cong, thong cong, nhung don
hang cong » dang cong, hang nong, bang cong
ho thiet » hoc thiet, hoa thiet, so thiet

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 ((nhung cong) or (hang cong)) dang ((toan ban) or (van ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho thiet hach - hanh trinh quan ((nhung cong) OR (hang cong)) dang ((toan ban) OR (van ban)).
• Adding a wildcard symbol may retrieve word variants: ho thiet hach - hanh trinh quan ((nhung cong) or (hang cong)) dang ((toan ban) or (van ban))*.