Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
nang mai » nang ma, nang tai, lang mai
tai cua » thai cua, tai cuc, tri cua
han tai » hang tai, nhan tai, van tai
cua tre » cua te, cuu tre, cua triet
vu cham » va cham, vu kham, tu cham
hieu vu » hieu va, hieu ve, hieu su
mai hoi » mai khoi, dai hoi, lai hoi
y nang » ky nang, ly nang, v nang
lo van » le van, vo van, do van
so van » su van, vo van
lo va » lao va, ly va, le va

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 y nang mai hoi. hieu vu cham ((lo va) or (((lo van) or (so van)))) han tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang mai hoi. hieu vu cham ((lo va) OR (((lo van) OR (so van)))) han tai cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach y nang mai hoi. hieu vu cham ((lo va) or (((lo van) or (so van)))) han tai cua tre*.