A "request" does not retrieve all of the content from a website - it simply opens a channel to perform subsequent operations. To get the content, you need to explicit get it, eg
SQL> set serverout on
SQL> declare
2 l_url varchar2(100) := 'http://www.oracledba.co.uk';
3 l_req utl_http.req;
4 l_resp utl_http.resp;
5 l_text varchar2(32767);
6 begin
7 l_req := utl_http.begin_request(l_url);
8 l_resp := utl_http.get_response(l_req);
9
10 -- loop through the data coming back
11 begin
12 loop
13 utl_http.read_text(l_resp, l_text, 32766);
14 dbms_output.put_line(l_text);
15 end loop;
16 exception
17 when utl_http.end_of_body then
18 utl_http.end_response(l_resp);
19 end;
20 end;
21 /