Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hanh tai » thanh tai, hang tai, han tai
hanh dao » lanh dao, thanh dat, thanh dam
cuc ban » cua ban, cac ban, cuu ban
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
ve pham » vi pham, ve phan, ve phat
sang ma » tang ma, nang ma, sang tao
ky sang » ky nang, ky dang, ky tang
ma hoi » mai hoi, xa hoi, ma hoa
v pham » vi pham, d pham

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky sang ma hoi. hieu ((ve pham) OR (v pham)) cuc ban ((hanh dao) or (hanh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky sang ma hoi. hieu ((ve pham) OR (v pham)) cuc ban ((hanh dao) OR (hanh tai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky sang ma hoi. hieu ((ve pham) OR (v pham)) cuc ban ((hanh dao) or (hanh tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ky sang ma hoi. hieu ((ve pham) OR (v pham)) cuc ban ((hanh dao) or (hanh tai)) cua tre*.