Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sang mai » sang ma, sang tai, lang mai
mai khoi » mai khoa, tai khoa, cac khoi
sach ky » sac ky, sach y, sach ty
danh va » doanh va, hanh va, anh va
va danh » va dinh, va dan, va hanh
cam tuc » cam tu, nam thuc, dam thuc
hieu va » lieu va, hieu qua
hieu ve » hieu van
ky sang » ky nang, ky dang, ky tang
cau tre » cau tren, cau treo, cau tra
va cau » van cau, va cac, va dau

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 ky sang mai khoi. ((hieu ve) or (hieu va)) ((cam tuc) OR (cam xuc)) va danh va cau tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky sang mai khoi. ((hieu ve) OR (hieu va)) ((cam tuc) OR (cam xuc)) va danh va cau tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky sang mai khoi. ((hieu ve) or (hieu va)) ((cam tuc) OR (cam xuc)) va danh va cau tre*".