Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » thien van, lieu va, hieu ve
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 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 van) OR (hieu va)) cau tuc va hanh tai cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky tang xa hoi. ((hieu van) 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 van) OR (hieu va)) cau tuc va hanh tai cua te*.