En la ayuda de Delphi encontré esto...
procedure TForm1.Button1Click(Sender: TObject);
begin
FindDialog1.Position := Point(RichEdit1.Left + RichEdit1.Width, RichEdit1.Top);
FindDialog1.Execute;
end;
procedure TForm1.FindDialog1Find(Sender: TObject);
var
FoundAt: LongInt;
StartPos, ToEnd: Integer;
begin
with RichEdit1 do
begin
{ begin the search after the current selection if there is one }
{ otherwise, begin at the start of the text }
if SelLength <> 0 then
StartPos := SelStart + SelLength
else
StartPos := 0;
{ ToEnd is the length from StartPos to the end of the text in the rich edit control }
ToEnd := Length(Text) - StartPos;
FoundAt := FindText(FindDialog1.FindText, StartPos, ToEnd, [stMatchCase]);
if FoundAt <> -1 then
begin
SetFocus;
SelStart := FoundAt;
SelLength := Length(FindDialog1.FindText);
end;
end;
end;
Suerte...
