Perhaps you should try some spelling variations:
doanh van » doan van, doanh va, doanh ban
cam truc » cau truc, nam truc, lam truoc
va doanh » van doanh, vay doanh, va danh
tu sach » thu sach, su sach, te sach
ly nang » ky nang, ly hang, ly vang
ty hang » ly hang, ty xang, thi hang
hieu va » lieu va, hieu qua
truc va » thuc va, thuc vat, trung va
van cuu » van cau, van chu, van cu
cuu tre » cua tre, cau tren, cau treo
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ly nang) or (ty hang)) xa hoi. hieu va cam truc va doanh van cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ly nang) OR (ty hang)) xa hoi. hieu va cam truc va doanh van cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ((ly nang) or (ty hang)) xa hoi. hieu va cam truc va doanh van cuu tre*.