Perhaps you should try some spelling variations:
tan hanh » tan thanh, tang hanh, toan hanh
te cach » ve cach, tu cach, te cac
te sach » toc sach
tu nang » tru nang, tu nong, tu nano
cho hoc » khoa hoc
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
cua chu » sua chua
ve cac » va cac, vien cac
vi cua » vai cua, di cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((te cach) OR (te sach)) tu nang ((cho hoc) OR (co hoc)). hieu ve cac duc tan hanh vi cua chu~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te cach) OR (te sach)) tu nang ((cho hoc) or (co hoc)). hieu ve cac duc tan hanh vi cua chu~".
• Adding a wildcard symbol may retrieve word variants: ((te cach) OR (te sach)) tu nang ((cho hoc) or (co hoc)). hieu ve cac duc tan hanh vi cua chu*.