Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hanh vai » hanh vi, hanh va, hanh tai
hieu va » lieu va, hieu qua
vai cua » dai cua, hai cua, lai cua
nang xa » nang x, lang xa, nang ma
hieu ve » hieu van
y nang » ky nang, ly nang, v nang
bac va » ban va, bac ha, tac va
bao va » bao ve, tao va, ban va
cua te » cua tu

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang xa hoi. ((hieu ve) OR (hieu va)) cac ((bac va) OR (bao va)) hanh vai cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang xa hoi. ((hieu ve) or (hieu va)) cac ((bac va) OR (bao va)) hanh vai cua te~".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang xa hoi. ((hieu ve) or (hieu va)) cac ((bac va) OR (bao va)) hanh vai cua te*.