求助，请问如何检索以,分隔的重复项？

Option Explicit

Private Sub Command1_Click()
  Dim str As String
  Dim A
  Dim i As Integer
  Dim RenSenFlag As Boolean
  Dim LiLuFlag As Boolean

  
  str = "藜芦,人参,细辛,辛勺,"
  A = Split(str, ",")
  For i = 0 To UBound(A)
      If A(i) = "人参" Then RenSenFlag = True: Exit For
  Next
  For i = 0 To UBound(A)
      If A(i) = "藜芦" Then LiLuFlag = True: Exit For
  Next
  If RenSenFlag And LiLuFlag Then
     MsgBox "str中同时含有人参和藜芦", vbCritical + vbOKOnly, "警告"
  End If
End Sub

您好，请问我的str有很多行，而且内容不固定，可以做到随时更新吗？