Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
ban thanh » ban hanh, ban hang
vu khach » vu khanh, vu khac, vay khach
thu sach » tu sach, thuat sach, thuoc sach
thuc ban » thuoc ban, thuc dan, thu ban
cam thuc » am thuc, nam thuc, cam thu
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
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) OR (nang ma)) hoi. lieu va cam thuc ban thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu khach) OR (thu sach)) ky ((nang xa) OR (nang ma)) hoi. lieu va cam thuc ban thanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu khach) or (thu sach)) ky ((nang xa) OR (nang ma)) hoi. lieu va cam thuc ban thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((vu khach) or (thu sach)) ky ((nang xa) OR (nang ma)) hoi. lieu va cam thuc ban thanh vai cua tre*.