Queries causing high physical read

SELECT schema, sql_text, disk_reads, round(cpu,2) FROM (SELECT s.parsing_schema_name schema, t.sql_id, t.sql_text, t.disk_reads, t.sorts, t.cpu_time/1000000 cpu, t.rows_processed, t.elapsed_time FROM v$sqlstats t join v$sql s on(t.sql_id = s.sql_id) WHERE parsing_schema_name = 'SCOTT' ORDER BY disk_reads DESC) WHERE rownum <= 5;