Make a query with the following SQL:
SELECT tblMain.Address, tblMain.Purchaser, tblMain.Plot, tblMain.Bedrooms
FROM tblMain
WHERE (((tblMain.Address) Like "*" & [KeywordForAddress] & "*")) OR (((tblMain.Purchaser) Like "*" & [KeywordForPurchaser] & "*"));
--you may add more fields in the...