Perhaps you should try some spelling variations:
trung chan » trung phan, trong chan, trung can
hieu manh » chieu xanh, hieu nganh, dieu hanh
trong can » trong canh, trong chan, trong cac
dung cong » dung trong
cong thuc » cong tac
thuc toan » thuc trang, thuat toan, thuc thanh
hoc hieu » hoc thieu, hoc hien, doc hieu
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu manh - thanh ((trung chan) or (trong can)) dung cong thuc toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - thanh ((trung chan) OR (trong can)) dung cong thuc toan cao.
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - thanh ((trung chan) or (trong can)) dung cong thuc toan cao*.