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
va khac » va khao, va kha, vu khac
dat van » dao van, dat va, dam van
ma hoi » mai hoi, ma hoa, me hoi
va hac » van hac, va cac, va hoc
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ky nang ((ma hoi) or (xa hoi)). lieu ((va hac) OR (va khac)) dat van hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky nang ((ma hoi) OR (xa hoi)). lieu ((va hac) OR (va khac)) 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 (xa hoi)). lieu ((va hac) OR (va khac)) dat van hanh vi cua vat".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang ((ma hoi) or (xa hoi)). lieu ((va hac) OR (va khac)) dat van hanh vi cua vat*.