Some spammer keeps sending mails by changing domains and ip,all spf check passed and ip not in any rbl,in this case,sometimes spams miss catching. But i foud that sometimes these mails are all set to a same reply mail box,such as:

Reply-To: admin@dashujumaoyi.com

Then how to filter it by header filter-customs header filter??

String to search for "Reply-To: admin@dashujumaoyi.com" using Contians??

Or 

String to search for "@dashujumaoyi.com" ??