Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh tai » thanh tai, hang tai, han tai
sach ky » sac ky, sach y, sach ty
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
hieu ve » hieu van
hieu va » lieu va, hieu qua
cau tuc » cau truc, cau tu, cau luc
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua
tuc va » thuc va, truc va, tuc xa
cua te » cua tu

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 ky tang xa hoi. ((hieu ve) or (hieu va)) cau tuc va hanh tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky tang xa hoi. ((hieu ve) OR (hieu va)) cau tuc va hanh tai cua te.
• Adding a wildcard symbol may retrieve word variants: toc sach ky tang xa hoi. ((hieu ve) or (hieu va)) cau tuc va hanh tai cua te*.