Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
van hanh » van thanh, ban hanh, van anh
sach ky » sac ky, sach y, sach ty
van cac » van cau, van bac, dan cac
van hac » van hoc, van ha, van hai
dat van » dao van, dat va, dam van
ma hoi » mai hoi, xa hoi, me hoi
vi cua » vai cua, di cua

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: thuat sach ky nang ((ma hoi) OR (ma hoa)). hieu ((van cac) OR (van hac)) dat van hanh vi cua vat~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky nang ((ma hoi) or (ma hoa)). hieu ((van cac) OR (van hac)) dat van hanh vi cua vat~".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang ((ma hoi) or (ma hoa)). hieu ((van cac) OR (van hac)) dat van hanh vi cua vat*.