not all DDL in V$SQL

Hello, (oracle 9.2.0.8 on AIX5/3) I seem to be missing many SQL statements that recently executed (seconds) in V$SQL and/or V$SQLAREA. These are mostly CTAS (create table as select x, y, z, from table ab). Also the SELECT part of the CTAS is not visible as a separate statement. I see other DDL like truncate, create bitmap index, however no drop.