Hi Jose,

I am sorry as currently advance search only works for user profile. If you wish to have this feature, you can write this in our Voices page here: http://stackideas.com/voices/easysocial and our developers will get back to you.

As for customization, you can edit this file: .../components/com_easysocial/themes/wireframe/groups/default.items.group.php . I am sorry as I can't assist you with the customization right now since our hands are pretty tied with our existing development. I will try get back to you once I have my spare time.

Thanks and have a nice day ahead.