Its very easy. Just go with stocks which have action. Like idea was in focus because of news regarding selling tower business. So it resulted in negative sentiment & attracted big volumes. I still got late & regret not entering on time.
Jaypee associates was in news, rcomm in news.
But mind you, dont ever buy or sell a stock whenever it declares results during market hours. Stay away else you will lose 90% of the time.
These days exchanges are not transparent as they used to be many years back. Yes markets are no more transparent now. I feel price movement is controlled by exchanges , many times especially during high volatility when results of a stock are declared.