Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh di » thanh doi, thanh de, thanh do
ky tang » ky nang, ky dang, kho tang
tang ha » lang ha, tang ma, trung ha
tham so » tham do, than so, cham soc
cua tre » cua te, cuu tre, cua triet
te cac » tu cac, ve cac, te cao
ha hoi » hoa hoi, ha noi, xa hoi
ham so » nam so, cham soc

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te cac ky tang ha hoi. hieu qua ((tham so) OR (ham so)) ban thanh di ((cua tre) or (cua vat))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te cac ky tang ha hoi. hieu qua ((tham so) OR (ham so)) ban thanh di ((cua tre) OR (cua vat))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te cac ky tang ha hoi. hieu qua ((tham so) OR (ham so)) ban thanh di ((cua tre) or (cua vat))*".