Not able to skip bad rows when select xml search and write out good rows

My script got the following error when try to write out or insert to a table:
ORA-31011: XML parsing failed
ORA-19202: Error occurred in XML processing
LPX-00216: invalid character 146 (0x92)
Error at line 87

the select contains xml type reading in and write out to varchar 4000, how can skip the bad rows and write the good rows out in my code?

select c.1,c.2,p.1,x.1 '//app:coverage/'||m.xml_name||'/@answer' as xpath,,extractvalue(x.xml_data,'//app:coverage/'||m.xml_name||'/@answer','xmlns:app="http://www.xyz.com/application/data"') as COVER from c,p,x