Hey Tejas,
I just wanted to know if I got you right. You mean sourcing profiles from the job portals, right? Now, that comes with a bit of practice. And when you keep doing it, you will know the basics. Whatever your search mandate is, try breaking it into small parts. For example, if you need someone for Event Management, then you need to think about "Direct marketing", "Roadshows", Interactive marketing!! The reason is that these search mandates will only work if the candidates have put their search nodes! You need to think from their shoes and then try hitting the right search word. Otherwise, what will happen is if I search for event management, then the site would throw me profiles containing C, C++ :-)
I hope you got a bit of an idea.. take care, pal.
Sunil