Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
van hanh » ban hanh, van anh, van ban
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
cua tre » cua te, cuu tre, cua triet
te sai » te tai, te lai, te hai
te bai » te bao, te tai, te ban
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 sai) OR (te bai)) ky nang x ho. hieu va cac tuc ((van hanh) OR (van thanh)) vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sai) or (te bai)) ky nang x ho. hieu va cac tuc ((van hanh) OR (van thanh)) vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((te sai) or (te bai)) ky nang x ho. hieu va cac tuc ((van hanh) OR (van thanh)) vi cua tre*.