Simple enough

Sub DeleteToPhrase()
Const strPhrase As String = "the phrase to find"
Dim oRng As Range
    Set oRng = ActiveDocument.Range
    With oRng.Find
        Do While .Execute(FindText:=strPhrase, MatchCase:=True)
            oRng.Collapse 1
            oRng.start = ActiveDocument.Range.start
            oRng.Text = ""
            Exit Do
        Loop
    End With
lbl_Exit:
    Exit Sub
End Sub