Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
mai hoi » mai khoi, dai hoi, mai doi
lai hoi » dai hoi, lai hoa, lai roi
sach ky » sac ky, sach y, sach ty
va danh » va dinh, va dan, va hanh
doi dau » doan dau
cac luc » cau luc, coc luc, cac nuoc
luc va » duc va, tuc va, loc va
di dau » bi dau, di du, di cau

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 ((mai hoi) OR (lai hoi)). lieu va cac luc va danh ((di dau) or (doi dau)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky nang ((mai hoi) OR (lai hoi)). lieu va cac luc va danh ((di dau) OR (doi dau)) tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky nang ((mai hoi) OR (lai hoi)). lieu va cac luc va danh ((di dau) or (doi dau)) tren".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang ((mai hoi) OR (lai hoi)). lieu va cac luc va danh ((di dau) or (doi dau)) tren*.