Loop through files, find value in column

[Nu2Java]

Hello, I am trying to loop through a directory of files to get a list of file names based on a value from column A. I have a list of parts in column A (2,467 to be exact). I want to search every filename and its contents. I want to then output some listing for what was found but I am getting confused doing this entire task. My results come out blank. Hopefully this makes sense... Thanks for any help!

Column A example:
A1 = Apples
A2 = Oranges
A3 = Pears

Search files and output results of find.

File1: (Contains Apples, Oranges, Pears)
File2: (Contains Pears)
File3: (Contains Apples, Oranges)
File4: (N/A)
File5: (Contains Pears, Apples)
File6: (N/A)
File7: (Contains Oranges)

Sub StringExistsInFile()

    Dim theString
    Dim path As String
    Dim StrFile As String
    Dim fso As New FileSystemObject
    Dim file As TextStream
    Dim line As String
    Dim amount As Long
    Dim theResult As String
    Dim sHostName As String
    Dim i As Long

    
    path = "P:\prg\"
    StrFile = Dir(path & "*.dp")
    
    
    Sheets("PartList").Activate
    

  Do While StrFile <> ""
 
    Set file = fso.OpenTextFile(path & StrFile)
        
    Do While Not file.AtEndOfStream
        theString = Cells(Rows.Count, "A").End(xlUp).Row
        For i = 1 To Rows.Count
            line = file.ReadAllLines()
            If InStr(1, line, theString, vbTextCompare) > 0 Then
            MsgBox theString
            Userform1.ListBox1.AddItem (StrFile & ":" & theString)
              
            End If
        Next i
    Loop
        
    file.Close
    Set file = Nothing
    Set fso = Nothing
    StrFile = Dir()
        
  Loop
    
End Sub