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

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) or (xa hoi)). hieu ve pham cuc ban ((hanh dao) or (han tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky sang ((ma hoi) OR (xa hoi)). hieu ve pham cuc ban ((hanh dao) OR (han tai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach ky sang ((ma hoi) or (xa hoi)). hieu ve pham cuc ban ((hanh dao) or (han tai)) cua tre*.