Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
minh hai » minh khai, tinh hai, manh hai
hieu van » hieu va, thien van, lieu va
danh hai » dang hai, lanh hai, manh hai
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
cuc ban » cua ban, cac ban, cuu ban
van cam » van nam, van lam, van cau
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ky lang xa hoi. hieu van cam ((cuc ban) or (duc van)) ((danh hai) or (minh hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ky lang xa hoi. hieu van cam ((cuc ban) OR (duc van)) ((danh hai) OR (minh hai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: hoc sach ky lang xa hoi. hieu van cam ((cuc ban) or (duc van)) ((danh hai) or (minh hai)) cua tre*.