Selection.Paragraphs(1) will work. There is no need to select the paragraph. You do however have to stop the search when the range has been processed.
Code:
Sub TestV3()
'
'
Dim Rng As Range
Set Rng = Selection.Paragraphs(1).Range
With Rng.Find
.ClearFormatting
.Replacement.ClearFormatting
.Text = "[no?ooo~uo]"
.Replacement.Text = ""
.Wrap = wdFindStop 'stop the search
.Format = True
.Execute Replace:=wdReplaceAll
End With
Set Rng = Nothing
End Sub