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

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 ((cau tuc) OR (cau luc)) va hanh ((tai cua) or (tri cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky tang xa hoi. hieu van ((cau tuc) OR (cau luc)) va hanh ((tai cua) OR (tri cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky tang xa hoi. hieu van ((cau tuc) OR (cau luc)) va hanh ((tai cua) or (tri cua)) te".
• Adding a wildcard symbol may retrieve word variants: toc sach ky tang xa hoi. hieu van ((cau tuc) OR (cau luc)) va hanh ((tai cua) or (tri cua)) te*.