Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
tu sach » thu sach, su sach, te sach
ky lang » ky nang, ky dang, ky tang
lang ha » long ha
hieu vu » hieu va, hieu ve, hieu su
vu cham » va cham, vu kham, tu cham
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, tuc xa
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) or (thuoc sach)) ky lang ha noi. hieu vu cham ((tuc va) or (duc va)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ky lang ha noi. hieu vu cham ((tuc va) OR (duc va)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ky lang ha noi. hieu vu cham ((tuc va) or (duc va)) hanh vi cua tre*.