Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thanh tai » thanh hai, thanh toan, doanh tai
toc sach » hoc sach, doc sach, nuoc sach
tai cua » thai cua, tai cuc, tri cua
hieu ve » hieu va, hieu van
ky dang » ky nang, ky danh
dang ma » dang mau, dang mam, dang mat
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
ve cam » ve cham, ve cac, va cam
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) or (thuoc sach)) ky dang ma hoi. hieu ve cam ((xuc va) or (luc va)) thanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) ky dang ma hoi. hieu ve cam ((xuc va) OR (luc va)) thanh tai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (thuoc sach)) ky dang ma hoi. hieu ve cam ((xuc va) or (luc va)) thanh tai cua tre*.