It sounds like there is no value in strResult when changed to use the userform value. Greg has shown how to use a userform value. He has not included the userform, which you will need to add to your document or modify the code to use the value selected from the userform. Userforms are difficult to reproduce in the forum.
Replace the Macro1 I provided earlier with
Code:
Sub Macro1()
'look for the value in the first column and return the value in the sixth column
Dim strResult As String
Dim strValue As String
strValue = InputBox("Enter the value to find")
If strValue = "" Then
MsgBox "No value entered or user cancelled"
GoTo lbl_Exit
End If
strResult = GetValue(strValue, 6)
FillBM "bookmarkname", strResult 'fill the named bookmark with the value
lbl_Exit:
Exit Sub
End Sub
which does not need a userform.