Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
phong cong » phong chong, thong cong, chong cong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
tranh cac » trinh cac, thanh cac, tranh cai
cong cong » cong dong, trong cong, dung cong
dan toan » van toan, dan than, 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: hoc thiet tach - canh tranh cac ((phong cong) or (cong cong)) dan toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - canh tranh cac ((phong cong) OR (cong cong)) dan toan ban*.