Perhaps you should try some spelling variations:
manh hanh » xanh hanh, danh thanh, minh thanh
toc sach » hoc sach, doc sach, thuoc sach
duc manh » suc manh, duc anh, duc minh
cho hoc » khoa hoc
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
cua cau » cua cac, cua chu, cua cay
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.

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) ky nang ((cho hoc) or (co hoc)). hieu ve cac duc manh hanh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky nang ((cho hoc) OR (co hoc)). hieu ve cac duc manh hanh vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ky nang ((cho hoc) or (co hoc)). hieu ve cac duc manh hanh vi cua cau*".