Code:
With Selection.Find
    .Text = vbCrLf & vbCrLf
    .Replacement.Text = ""
    .Forward = True
    .Wrap = wdFindContinue
    .Format = False
    .MatchCase = False
    .MatchWholeWord = False
    .MatchWildcards = False
    .MatchSoundsLike = False
    .MatchAllWordForms = False
End With
MsgBox Selection.Find.Execute
The above code returing false value. please help me to replace two ENTERS to one ENTER.