Search Engine in vb.Net

Question

ok.. take a look at this piece of code.. DataAdapter_RunNum2.SelectCommand.CommandText = _ "SELECT [Main Table].Date, " & _ "[Main Table].Remarks, " & _ "[Project Table].Name, " & _ "[Project Table].Number, " & _ "[Document Table].Type, " & _ "[File Table].Type, " & _ "[User Table].Name " & _ "FROM ((((([Main Table] " & _ "INNER JOIN [Project Table] " & _ "ON [Main Table].projectID = [Project Table].projectID) " & _ "INNER JOIN [Document Table] " & _ "ON [Main Table].documentID = [Document Table].documentID) " & _ "INNER JOIN [File Table] " & _ "ON [Main Table].fileID = [File Table].fileID) " & _ "INNER JOIN [User Table] " & _ "ON [Main Table].userID = [User Table].userID) " & _ "INNER JOIN [Company Table] " & _ "ON [Main Table].companyID = [Company Table].companyID) " & _ "WHERE [Main Table].[Running Number] = 5 " DataAdapter_RunNum2.SelectCommand.ExecuteNonQuery() DataAdapter_RunNum2.Fill(DataSet_RunNum2) i'm really confused.. * why is it i cannot change the number 5 to a '" & cboRunNum.Text & "'?.. whereby the cboRunNum has a list of numbers that can be used.. * what does "expr1, expr2.." refers to? * how do i make a search based on dates?.. as in between 20/07/2004 and 16/07/2004?.. what are the command codes like?.. can i put it as.. "WHERE [Main Table].date >= '" & cboStart.Text & "' " & _ "AND [Main Table].date <= '" & cboStop.Text & "' " & _ i tried it but it doesnt work.. anyone?.. help!..