Perhaps you should try some spelling variations:
sanh van » san van, anh van, canh van
truc van » truc va, thuc van, truc ban
van hanh » van thanh, ban hanh, van anh
so sanh » do sanh
hieu va » lieu va, hieu qua
hanh de » hanh ve, hanh kem
cua tre » cua te, cuu tre, cua triet
co hoi » co hoc, co loi
va cau » van cau, va cac, va dau
de cua » le cua, te cua, dieu cua
o hoc » co hoc, mo hoc, so hoc
dong » cong, dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sanh van dong ((co hoi) or (o hoc)). hieu va cau truc van hanh de cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh van dong ((co hoi) OR (o hoc)). hieu va cau truc van hanh de cua tre.
• Adding a wildcard symbol may retrieve word variants: so sanh van dong ((co hoi) or (o hoc)). hieu va cau truc van hanh de cua tre*.