Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vi » hanh vi, thanh va, thanh ve
tham soc » tham nuoc, thai son, ham so
cua tre » cua te, cuu tre, cua triet
tang ha » lang ha, trung ha, tang van
tang ma » mang may, tang van
vi cua » vai cua, di cua
te cac » tu cac, ve cac, te cao

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: te cac ky ((tang ha) OR (tang ma)) hoi. hieu qua ((tham soc) OR (cham soc)) ban thanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te cac ky ((tang ha) or (tang ma)) hoi. hieu qua ((tham soc) OR (cham soc)) ban thanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: te cac ky ((tang ha) or (tang ma)) hoi. hieu qua ((tham soc) OR (cham soc)) ban thanh vi cua tre*.