Find and Replace Routine not working

.net 2003
access 2003


What Iam Doing...

Taking a value from a field...fldMfgname
See if it exists in another table  txtFind...
If it does it is replaced with the txtReplace Value

Problem...
Ny Field value in fldMfgname keeps getting deleted to  "" or null


i.e.

What it should do:

tblVendNameFindReplace   =
txtFind         txtReplace
BUSS             BUSSMANN


tblData =
fldMfgname
BUSS


Replaced value  is  

BUSSMANN



iI keep getting the value in fldMfgname deleted...





Private Function AccessSandR()
        Dim conn As System.Data.OleDb.OleDbConnection
        Dim tblVendNameFindReplace As New DataTable
        Dim tblData As New DataTable

        conn = New System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Program Files\Dm2007\SkuCat.mdb")
        'make dataadapters
        Dim dac As New System.Data.OleDb.OleDbDataAdapter("SELECT fldId, txtFind, txtReplace FROM tblVendNameFindReplace ", conn)
        Dim dad As New System.Data.OleDb.OleDbDataAdapter("SELECT fldID, fldDid, fldMfgname, fldMfrnum, fldDescription FROM tblData", conn)
        Dim cb As New System.Data.OleDb.OleDbCommandBuilder(dad)
        'get the datables from Access
        dac.Fill(tblVendNameFindReplace)
        dad.Fill(tblData)
        'send updated table back to Access

        For Each drc As DataRow In tblVendNameFindReplace.Rows
            For Each drd As DataRow In tblData.Rows
                If Not IsDBNull(drd("fldMfgname")) Then drd("fldMfgname") = ReplaceWordsTemplate(drd("fldMfgname"), drc("txtFind"), drc("txtReplace"))
            Next
        Next
        dad.Update(tblData)
    End Function
   
    Private Function ReplaceWordsTemplate(ByVal SearchText As String, ByVal Token As String, ByVal ReplaceText As String) As String
        Dim newtext As String = ""
        newtext = SearchText.Replace(" " & Token & " ", " " & ReplaceText & " ")
        'return result after removing space added at the end
        Return newtext.Substring(0, newtext.Length - 1)
    End Function


Thanks
fordraiders