perhaps then your problem is the way you exported .... can you show us the export command? did you use owner= on the export command line?
bash-2.05$ imp myusername/mypassword IGNORE=y FROMUSER=QUYREC TOUSER=QUYREC FILE=/app5/oracle/backup/prt9dllo/quyrec.dmp
IMP-00034: Warning: FromUser "QUYREC" not found in export file