바로 밑의 폴더목록만 구하는거는
procedure TForm1.Button2Click(Sender: TObject);
var
    SearchRec: TSearchRec;
begin
    if FindFirst('C:HSR_JOB응용소스스트링 디비 그리드' + '*.*', faAnyFile , SearchRec) = 0 then begin
      repeat
         if (SearchRec.Attr and FaVolumeId <> FaVolumeID) then begin
            if (SearchRec.Attr and FaDirectory = FaDirectory) then begin
                if (SearchRec.Name <> '.')and(SearchRec.Name <> '..') then
                   Form1.ListBox1.Items.Add(SearchRec.Name);
            end;
         end;
      until FindNext(SearchRec) <> 0;
      FindClose(SearchRec);
    end;
end;

그리고 하위의 하위를 계속 찾는건 재귀호출을 쓰시면 됩니다.
procedure FileExtSearch(DirectoryList:string);
var
    SearchRec: TSearchRec;
begin
    if FindFirst(DirectoryList + '*.*', faAnyFile , SearchRec) = 0 then begin
      repeat
         if (SearchRec.Attr and FaVolumeId <> FaVolumeID) then begin
            if (SearchRec.Attr and FaDirectory = FaDirectory) then begin
                if (SearchRec.Name <> '.')and(SearchRec.Name <> '..') then begin
                   Form1.ListBox1.Items.Add('[폴더]' + DirectoryList + '' +SearchRec.Name);
                   FileExtSearch(DirectoryList + '' + SearchRec.Name);
                end;
            end
            else begin
               Form1.ListBox1.Items.Add('[' + DirectoryList + ']' +SearchRec.Name);
            end;
         end;
      until FindNext(SearchRec) <> 0;
      FindClose(SearchRec);
    end;
end;


procedure TForm1.Button1Click(Sender: TObject);
begin
    ListBox1.Clear;
    FileExtSearch('C:HSR_JOB응용소스스트링 디비 그리드');  //
end;
hsr//////////////////////////////////////////////////////////