Perhaps you should try some spelling variations:
toan hanh » toan thanh, toan anh, tran hanh
hieu van » thien van, lieu va, hieu ve
duc toan » duc tan, duc ton, duc hoan
te sach » toc sach
sach ly » sach y, sach lo, sach ty
ly nang » ky nang, ly hang, ly vang
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
vai cua » dai cua, lai cua, bai cua
hai cua » thai cua, dai cua, hoi 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 sach ly nang xa hoi. ((hieu van) OR (hieu va)) giao duc toan hanh ((vai cua) OR (hai cua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ly nang xa hoi. ((hieu van) OR (hieu va)) giao duc toan hanh ((vai cua) or (hai cua)) tre~".
• Adding a wildcard symbol may retrieve word variants: te sach ly nang xa hoi. ((hieu van) OR (hieu va)) giao duc toan hanh ((vai cua) or (hai cua)) tre*.