Perhaps you should try some spelling variations:
thuat sac » thuat sach, thuat san, thuat tac
van hanh » van thanh, ban hanh, van anh
hieu ve » hieu va, hieu van
cao suc » cao duc
hanh de » hanh ve, hanh kem
sac ky » cac ky, sai ky
de cua » le cua, te cua, dieu cua
cua te » cua tu
x hoi » xa hoi, o hoi, 5 hoi

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: thuat sac ky nang ((x hoi) OR (x ho)). hieu ve ((cao suc) OR (cao su)) van hanh de cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sac ky nang ((x hoi) OR (x ho)). hieu ve ((cao suc) or (cao su)) van hanh de cua te~".
• Adding a wildcard symbol may retrieve word variants: thuat sac ky nang ((x hoi) OR (x ho)). hieu ve ((cao suc) or (cao su)) van hanh de cua te*.