Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
nang o » nang co, nang ho, nang ro
va cam » va cham, va cac, va cao
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di cua
o hoi » co hoi, o hoc, o hai

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) or (thuat sach)) ky nang o hoi. hieu va cam ((xuc va) or (tuc va)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuat sach)) ky nang o hoi. hieu va cam ((xuc va) OR (tuc va)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuat sach)) ky nang o hoi. hieu va cam ((xuc va) or (tuc va)) hanh vi cua tre*.