Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van ban
tham xuc » tham nuoc, tham thuc, pham duc
van anh » van thanh, tuan anh, van minh
va tham » van tham, va cham, va thanh
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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) or (dac sac)) ky lang xa hoi. hieu va tham xuc ((van hanh) OR (van anh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (dac sac)) ky lang xa hoi. hieu va tham xuc ((van hanh) OR (van anh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (dac sac)) ky lang xa hoi. hieu va tham xuc ((van hanh) OR (van anh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (dac sac)) ky lang xa hoi. hieu va tham xuc ((van hanh) OR (van anh)) vi cua tre*.