Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
vu khach » vu khanh, vu khac, vay khach
thanh vi » hanh vi, thanh va, thanh ve
thu sach » tu sach, thuat sach, thuoc sach
thuc ban » thuoc ban, thuc dan, thu ban
cua tre » cua te, cuu tre, cua triet
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
vi cua » vai cua, di cua
va cam » va cham, va cao, va cai

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