There is currently no way to search for a certificate. You can only look
it up if you already know the serial number.
Dogtag 10 has a fresh API which makes searching very easy. I've started
designing a search interface here: http://freeipa.org/page/Cert_find
I was able to create a proof-of-concept (minus date options) using this
API in about 90 minutes.
Freeipa-devel mailing list