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
cac thuc » cach thuc, cac thu, can thuc
vai cua » dai cua, hai cua, lai cua
lang ha » long ha
lang xa » dang xay, lang van
cua tre » cua te, cuu tre, cua triet

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: ((vu khach) OR (thu sach)) ky ((lang xa) OR (lang ha)) hoi. lieu va cac 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 ((lang xa) OR (lang ha)) hoi. lieu va cac thuc ban thanh vai cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((vu khach) or (thu sach)) ky ((lang xa) OR (lang ha)) hoi. lieu va cac thuc ban thanh vai cua tre*.