Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
ky cau » ky chau, ke cau
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 (thuat sach)) y nang ma hoi. hieu ky cau ((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 (thuat sach)) y nang ma hoi. hieu ky cau ((tuc va) OR (duc va)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuat sach)) y nang ma hoi. hieu ky cau ((tuc va) or (duc va)) hanh vi cua tre*.