Perhaps you should try some spelling variations:
thieu tach » thien hach, chiet tach, chieu sach
trong mach » trong cac, trong minh, trong anh
hoc thieu » toc thieu, hoc hien
canh tang » anh tang, canh tranh, cang thang
mach toan » manh toan, hach toan, mach tuan
toan ban » van ban
tang su » tang suc, trang su, dang su

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thieu tach - canh tang su dung trong mach toan ban~.
• Adding a wildcard symbol may retrieve word variants: hoc thieu tach - canh tang su dung trong mach toan ban*.