Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
doanh van » doan van, doanh va, doanh ban
va doanh » van doanh, vay doanh, va danh
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
x hoi » xa hoi, o hoi, x ho

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 x hoi. ((lieu va) or (hieu qua)) pham duc va doanh van ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky nang x hoi. ((lieu va) OR (hieu qua)) pham duc va doanh van ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky nang x hoi. ((lieu va) or (hieu qua)) pham duc va doanh van ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang x hoi. ((lieu va) or (hieu qua)) pham duc va doanh van ((cua tre) OR (cuu tre))*.