Cái này cũng là VBA mà là function
Public Function KeyWordValidation(Bang1 As Range, data As Range) As String
Dim sKeyWord As String
Dim vKeyWord As Variant
Dim sData As String
Dim sPattern As String
Dim i As Long
sKeyWord = ""
sData = data.Value
vKeyWord = Bang1.Value
For i = 1 To UBound(vKeyWord)
sPattern = vKeyWord(i, 1)
If InStr(1, sData, sPattern, vbTextCompare) <> 0 Then
If Len(sKeyWord) = 0 Then
sKeyWord = sPattern
Else
sKeyWord = sKeyWord + "," + sPattern
End If
End If
Next
KeyWordValidation = sKeyWord
End Function