Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
hanh va » hang va, hanh vi
xuc van » duc van, luc van, xuc ban
hieu va » lieu va, hieu qua
cuu tre » cua tre, cau tren, cau treo
nang xa » lang xa, nang ma, mang xa
va cam » va cham, va cac, va cao
va cuu » va cau, va chu, va huu

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) or (hoc sach)) ky ((nang xa) or (nang x)) hoi. hieu va cam xuc van hanh va cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (hoc sach)) ky ((nang xa) OR (nang x)) hoi. hieu va cam xuc van hanh va cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (hoc sach)) ky ((nang xa) or (nang x)) hoi. hieu va cam xuc van hanh va cuu tre*.