Perhaps you should try some spelling variations:
vu khach » vu khanh, vay khach, cua khach
van hanh » van thanh, ban hanh, van anh
vu khac » vu kham, vu khanh, bui khac
hieu ve » hieu va, hieu van
dam tuc » dam thuc, dao tuc, nam thuc
cua tre » cua te, cuu tre, cua triet
dam tu » nam tu, cam tu, tam tu
vi cua » vai cua, di cua
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: ((vu khach) or (vu khac)) ky nang x hoi. hieu ve ((dam tuc) or (dam tu)) van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu khach) OR (vu khac)) ky nang x hoi. hieu ve ((dam tuc) OR (dam tu)) van hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((vu khach) or (vu khac)) ky nang x hoi. hieu ve ((dam tuc) or (dam tu)) van hanh vi cua tre*.