Workbooks.Open Filename:="Полный путь\Книга1.xls", UpdateLinks:=False, ReadOnly:=True
Set Kniga1_List1 = Workbooks("Книга1.xls").Worksheets("Лист1")

With Kniga1_List1

Sub test()
Dim dicObj As Object
Dim i&, iLastRow&
Dim Kniga1_List1 As Worksheet

Set Kniga1_List1 = Workbooks.Open("Книга1.xls").Worksheets("Лист1")  'Open добавлено мной
Set dicObj = CreateObject("scripting.dictionary")
dicObj.comparemode = 1
With Sheets("Лист1")
For i = 5 To .Cells(.Rows.Count, "C").End(xlUp).Row
dicObj.Item(.Cells(i, "C").Value) = 0
Next i
End With
With Kniga1_List1
For i = 4 To .Cells(.Rows.Count, "C").End(xlUp).Row
If Not dicObj.exists(.Cells(i, "C").Value) Then 'если нет слова, то добавляем его в словарь
dicObj.Item(.Cells(i, "C").Value) = 0
iLastRow = Cells(Rows.Count, 1).End(xlUp).Row + 1
.Range("A" & i & ":C" & i).Copy Cells(iLastRow, 1)
End If
Next i
End With
Workbooks("Книга1.xls").Close False 'добавлено мной
End Sub

Sub ClearStr()
Dim lngI As Long

    ClearWord = "ааа, ббб, ввв"
    
For lngI = Cells(Rows.Count, 3).End(xlUp).Row To 5 Step -1 
     If InStr(ClearWord, Cells(lngI, 3)) > 0 Then Rows(lngI).ClearContents
Next lngI
End Sub

7|  Range("B2:B65536").AdvancedFilter