Perhaps you should try some spelling variations:
dung phuong » dung thuong, bang phuong, dung chung
thiet hach » thien hach, thuyet hach, thiet hai
truong cua » truong ca, truong quan, huong cua
truong cao » truong dai
hoc thiet » hoc thieu, hoc thuyet, hoc hien
danh toan » manh toan, anh toan, dang toan
dan toan » van toan, dan than, manh toan

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 hach - thanh ((truong cua) or (truong cao)) dung phuong ((danh toan) OR (dan toan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet hach - thanh ((truong cua) OR (truong cao)) dung phuong ((danh toan) OR (dan toan)) tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet hach - thanh ((truong cua) or (truong cao)) dung phuong ((danh toan) OR (dan toan)) tap".
• Adding a wildcard symbol may retrieve word variants: hoc thiet hach - thanh ((truong cua) or (truong cao)) dung phuong ((danh toan) OR (dan toan)) tap*.