Perhaps you should try some spelling variations:
cham luc » nhan luc, cham cuu, chat lua
van hanh » van thanh, ban hanh, van anh
hanh doi » thanh doi, hanh noi, hang doi
su sach » vu sach
so sach » so sanh, bo sach, co sach
doi cuu » doi cua, doi cuoc
cuu tre » cua 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.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ky nang x hoi. hieu qua ((cham luc) OR (cham soc)) van hanh doi cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (so sach)) ky nang x hoi. hieu qua ((cham luc) OR (cham soc)) van hanh doi cuu tre~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) ky nang x hoi. hieu qua ((cham luc) OR (cham soc)) van hanh doi cuu tre*.