Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
van hanh » ban hanh, van anh, van ban
cac xuc » cam xuc, cac nuoc, chat xuc
vai cuu » vai cua
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
may hoi » may thoi, tay hoi, mai hoi
cuu tre » cua tre, cau tren, cau treo
sai ky » sac ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sai ky)) mang may hoi. hieu va cac xuc ((van hanh) OR (van thanh)) vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sai ky)) mang may hoi. hieu va cac xuc ((van hanh) OR (van thanh)) vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sai ky)) mang may hoi. hieu va cac xuc ((van hanh) OR (van thanh)) vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sai ky)) mang may hoi. hieu va cac xuc ((van hanh) OR (van thanh)) vai cuu tre*.