[Plugin: Another WordPress Classifieds Plugin] Integrate with WordPress default search?

Is there some kind of function I can use to integrate AWCP with the default WordPress search? I don’t like the idea of having ‘search classifieds’ and ‘search site’.

I’ve looked at a few plugins but I’m not sure of the taxonomy structure or other unique terms that I could use for integration.

http://ww.wp.xz.cn/extend/plugins/another-wordpress-classifieds-plugin/