Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, lai cua, bai cua
hai cua » thai cua, dai cua, hoi cua
ma hoi » mai hoi, xa hoi, ma hoa
cac bo » bac bo, cac co
bo va » bao va, do va, so va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ky nang ma hoi. ((hieu va) or (hieu qua)) cac bo va hanh ((vai cua) OR (hai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky nang ma hoi. ((hieu va) OR (hieu qua)) cac bo va hanh ((vai cua) OR (hai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky nang ma hoi. ((hieu va) or (hieu qua)) cac bo va hanh ((vai cua) OR (hai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky nang ma hoi. ((hieu va) or (hieu qua)) cac bo va hanh ((vai cua) OR (hai cua)) triet*.