Perhaps you should try some spelling variations:
sach nhiet » sach nghiep, sach thieu, cach thiet
nhiet nang » nhiet dong, viet nang, nhieu tang
cham luc » cham soc, nhan luc, cham cuu
chat cua » nhat cua, chat va, chat huu
van hanh » van thanh, ban hanh, van anh
hanh va » hang va, hanh vi
so sach » so sanh, bo sach, co sach
van hoe » van hoc, van hieu, van hien
va cua » va chua, via cua, ca cua
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach nhiet nang ((van hoe) or (van hoa)). hieu qua ((cham luc) or (chat cua)) van hanh va cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach nhiet nang ((van hoe) OR (van hoa)). hieu qua ((cham luc) OR (chat cua)) van hanh va cua tu.
• Adding a wildcard symbol may retrieve word variants: so sach nhiet nang ((van hoe) or (van hoa)). hieu qua ((cham luc) or (chat cua)) van hanh va cua tu*.