Perhaps you should try some spelling variations:
hieu manh » chieu xanh, hieu nganh, dieu hanh
canh manh » canh tranh, cach mang, van manh
lanh manh » lanh tranh, lan anh, van manh
tong cong » trong cong, cong cong, dung cong
bang cong » dang cong, bang song, hang cong
hoc hieu » hoc thieu, hoc hien, doc hieu
tap toan » tap doan, tap quan, bai 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 hieu manh - ((canh manh) or (lanh manh)) cua ((tong cong) or (bang cong)) tap toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - ((canh manh) OR (lanh manh)) cua ((tong cong) OR (bang cong)) tap toan ban.
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - ((canh manh) or (lanh manh)) cua ((tong cong) or (bang cong)) tap toan ban*.