Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
tham xuc » tham nuoc, tham thuc, pham duc
va triet » va thiet, va trien, ve triet
ky tang » ky nang, ky dang, kho tang
hieu va » lieu va, hieu qua
xuc van » duc van, luc van, xuc ban
ky lang » ky nang, ky dang, tay lang
cua tre » cua te, cuu tre, cua triet
va tham » van tham, va cham, va thanh
ha hoi » hoa hoi, ha noi, xa hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ky lang) or (ky tang)) ha hoi. hieu va tham xuc van hanh vi ((cua tre) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ky lang) OR (ky tang)) ha hoi. hieu va tham xuc van hanh vi ((cua tre) OR (va triet)).
• Adding a wildcard symbol may retrieve word variants: toc sach ((ky lang) or (ky tang)) ha hoi. hieu va tham xuc van hanh vi ((cua tre) or (va triet))*.