Perhaps you should try some spelling variations:
thanh tuong » thanh thuong, thanh tung, thanh huong
thiet danh » thien danh, thien anh, thien dang
hoc thiet » hoc thieu, hoc thuyet, hoc hien
nang cong » nang song, dang cong, bang cong
tuong va » truong va, thuong va, luong va
dan toan » van toan, dan than, manh toan
va nang » van nang, da nang, cam nang

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet danh - thanh tuong va nang cong ((dan toan) OR (tinh toan)) tap~.
• Adding a wildcard symbol may retrieve word variants: hoc thiet danh - thanh tuong va nang cong ((dan toan) or (tinh toan)) tap*.