Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
hieu ve » hieu van
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang
soc va » hoc va, loc va, doc va
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 ((y nang) OR (v nang)) xa hoi. ((hieu ve) or (hieu va)) cham soc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((y nang) OR (v nang)) xa hoi. ((hieu ve) OR (hieu va)) cham soc va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((y nang) OR (v nang)) xa hoi. ((hieu ve) or (hieu va)) cham soc va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) OR (v nang)) xa hoi. ((hieu ve) or (hieu va)) cham soc va hanh vi cua tre*.