Perhaps you should try some spelling variations:
su sach » so sach, vu sach
hai cua » thai cua, dai cua, hoi cua
vai cua » dai cua, lai cua, bai cua
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
van hac » van hoc, van ha, van hai
sach ky » sac ky, sach y, sach ty
van cac » van cau, van bac, dan cac
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ma hoi. hieu ((van cac) OR (van hac)) thuc va hanh ((vai cua) OR (hai cua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ma hoi. hieu ((van cac) or (van hac)) thuc va hanh ((vai cua) OR (hai cua)) tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ma hoi. hieu ((van cac) or (van hac)) thuc va hanh ((vai cua) OR (hai cua)) tre*.