Selection.Find.Execute Replace:=wdReplaceAll

wdoc2->ActiveWindow->Selection->Find->Execute(  );

VARIANT_BOOL Execute (
        VARIANT * __FindText = &vtMissing,
        VARIANT * MatchCase = &vtMissing,
        VARIANT * MatchWholeWord = &vtMissing,
        VARIANT * MatchWildcards = &vtMissing,
        VARIANT * MatchSoundsLike = &vtMissing,
        VARIANT * MatchAllWordForms = &vtMissing,
        VARIANT * Forward = &vtMissing,
        VARIANT * Wrap = &vtMissing,
        VARIANT * Format = &vtMissing,
        VARIANT * ReplaceWith = &vtMissing,
        VARIANT * Replace = &vtMissing,
        VARIANT * MatchKashida = &vtMissing,
        VARIANT * MatchDiacritics = &vtMissing,
        VARIANT * MatchAlefHamza = &vtMissing,
        VARIANT * MatchControl = &vtMissing );