If you see such error
ORA-39181: Only partial table data may be exported due to fine grain access control on "OE"."PURCHASEORDER"
during expdp you need to check if the user has the right privileges (EXEMPT ACCESS POLICY):
<sql> SELECT * FROM DBA_SYS_PRIVS WHERE GRANTEE ='DUMPUSER'
If it does not have this permission, add it using the command:
<sql> GRANT EXEMPT ACCESS POLICY TO DUMPUSER;