Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hieu van » hieu va, thien van, lieu va
tuan xuc » quang xuc, tuan khuc, toan xac
van tuan » van quan, van ban, anh tuan
hoc sach » hoc sinh, hoc cac, hoc anh
ty nang » ty xang, ty hang, ly nang
va dinh » van dinh, va kinh, va tinh
dinh di » dinh du, dinh vi, danh di
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc va
di cua » dai cua, doi cua, de 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 (hoc sach)) ((ty nang) or (ky nang)) xa hoi. hieu van tuan xuc va dinh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) ((ty nang) OR (ky nang)) xa hoi. hieu van tuan xuc va dinh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) ((ty nang) or (ky nang)) xa hoi. hieu van tuan xuc va dinh di cua tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (hoc sach)) ((ty nang) or (ky nang)) xa hoi. hieu van tuan xuc va dinh di cua tre*.