Perhaps you should try some spelling variations:
ban thanh » ban hang
vu khach » vu khanh, vu khac, vay khach
thu sach » tu sach, thuat sach, thuoc sach
cam thuc » am thuc, nam thuc, cam thu
ban hanh » ban hang
nang xa » nang x, lang xa, nang ma
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao

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 (thu sach)) ky nang xa hoi. lieu va cam thuc ((ban thanh) OR (ban hanh)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu khach) OR (thu sach)) ky nang xa hoi. lieu va cam thuc ((ban thanh) OR (ban hanh)) vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu khach) or (thu sach)) ky nang xa hoi. lieu va cam thuc ((ban thanh) OR (ban hanh)) vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((vu khach) or (thu sach)) ky nang xa hoi. lieu va cam thuc ((ban thanh) OR (ban hanh)) vai cua tre*.