Perhaps you should try some spelling variations:
thiet danh » thien danh, thien anh, thien dang
hoc thiet » hoc thieu, hoc thuyet, hoc hien
trung van » truong van, trung va, trung tuan
trong van » trong cac
nang cong » nang song, dang cong, bang cong
manh toan » thanh toan, anh tuan, tinh toan
dan toan » van toan, dan than, xuan 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 danh - thanh ((trung van) OR (trong van)) nang cong ((dan toan) or (manh toan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet danh - thanh ((trung van) OR (trong van)) nang cong ((dan toan) OR (manh toan)) tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet danh - thanh ((trung van) OR (trong van)) nang cong ((dan toan) or (manh toan)) tap".
• Adding a wildcard symbol may retrieve word variants: hoc thiet danh - thanh ((trung van) OR (trong van)) nang cong ((dan toan) or (manh toan)) tap*.