Hi all, can any one help me optimize this code. cause is make my program slow

Code:
For i = LBound(WordsArray) To UBound(WordsArray)
        For j = LBound(CommaArray) To UBound(CommaArray)
            If InStrB(CommaArray(j), WordsArray(i)) <> 0 Then
            k = k + 1
            ReDim Preserve strTemp(1 To k)
            strTemp(k) = CommaArray(j)
            End If
        Next j
    Next i