Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
ban hanh » ban hang
chat xuc » chat huu, cam xuc, chao xu
hieu van » hieu va, thien van, lieu va
xuc ban » duc ban, cuc ban, quoc ban
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
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 ty ((nang xa) or (nang ma)) hoi. ((hieu ve) OR (hieu van)) chat xuc ban hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((nang xa) OR (nang ma)) hoi. ((hieu ve) OR (hieu van)) chat xuc ban hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty ((nang xa) or (nang ma)) hoi. ((hieu ve) OR (hieu van)) chat xuc ban hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((nang xa) or (nang ma)) hoi. ((hieu ve) OR (hieu van)) chat xuc ban hanh vi cua tre*.