Perhaps you should try some spelling variations:
day thanh » dao thanh, dat thanh, da thanh
vu khach » vu khanh, vu khac, vay khach
khach ky » hanh ky, thanh ky
dao hanh » dao thanh, dang hanh, ban hanh
cua tre » cua te, cuu tre, cua triet
va cao » va cac, va co, va dao
va cam » va cham, va cac, va cai
di cua » dai cua, doi cua, de 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 ky nang x hoi. hieu ((va cam) OR (va cao)) thuc ((dao hanh) or (day thanh)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu khach ky nang x hoi. hieu ((va cam) OR (va cao)) thuc ((dao hanh) OR (day thanh)) di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu khach ky nang x hoi. hieu ((va cam) OR (va cao)) thuc ((dao hanh) or (day thanh)) di cua tre".
• Adding a wildcard symbol may retrieve word variants: vu khach ky nang x hoi. hieu ((va cam) OR (va cao)) thuc ((dao hanh) or (day thanh)) di cua tre*.