Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hoc sach » hoc sinh, hoc cac, hoc anh
va dinh » van dinh, va kinh, va tinh
cam luc » cam xuc, cau luc
hieu va » lieu va, hieu qua
va cam » va cham, va cac, va cao
v nang » va nang, vu nang, van nang
luc va » duc va, tuc va, loc va
di cua » doi cua, de cua, do cua
x hoi » xa hoi, o hoi, x ho

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)) v nang x hoi. hieu va cam luc va dinh ((di cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) v nang x hoi. hieu va cam luc va dinh ((di cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) v nang x hoi. hieu va cam luc va dinh ((di cua) or (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (hoc sach)) v nang x hoi. hieu va cam luc va dinh ((di cua) or (dai cua)) tre*.