Perhaps you should try some spelling variations:
hieu toc » hieu hoc, hieu tuc, sieu toc
van hanh » van thanh, ban hanh, van anh
cham xuc » cam xuc, chat xuc, pham duc
sach ty » sach y, sach tu, sach thu
tu sach » thu sach, su sach, te sach
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
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: tu sach ty ((nang xa) OR (lang xa)) hoi. hieu toc ((cham xuc) or (cham soc)) van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang xa) OR (lang xa)) hoi. hieu toc ((cham xuc) OR (cham soc)) van hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((nang xa) OR (lang xa)) hoi. hieu toc ((cham xuc) or (cham soc)) van hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((nang xa) OR (lang xa)) hoi. hieu toc ((cham xuc) or (cham soc)) van hanh vi cua tre*.