Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh quan » tinh quang, trinh luat, trinh han
nhung cong » dung cong, hang cong, nhung don
thong cong » trong cong, tong cong, thong thong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
ho thiet » hoa thiet, so thiet, hoc thieu
san toan » van toan, dan toan, manh toan
toan ban » van ban

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) or (hoc thiet)) tach - hanh trinh quan ((nhung cong) OR (thong cong)) san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho thiet) OR (hoc thiet)) tach - hanh trinh quan ((nhung cong) OR (thong cong)) san toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho thiet) or (hoc thiet)) tach - hanh trinh quan ((nhung cong) OR (thong cong)) san toan ban".
• Adding a wildcard symbol may retrieve word variants: ((ho thiet) or (hoc thiet)) tach - hanh trinh quan ((nhung cong) OR (thong cong)) san toan ban*.