my site appearing in search results and having many traffic from search , but from some i have been noticing that my site is disappeared from google search results. dont know the reason why? Plz help me ..
Google updating it's algorithm again recently, that's the answer I can give without knowing your website.
This may result due to change in Google Panda Algorithm. Google keep changing and updating its algorithm from the past couple of months and due to that many sites suffer.
Most probably your website is punished by Google Penguin which has been recently introduced. To make sure it is Penguin or not you can check your Google Webmasters account and if you receive warning regarding suspected back links then your website is a victim of Penguin. To resolve this you need to remove all poor quality back links for your website. If you have participated in paid back links services its time to stop all this because they all are poor quality back links. After removing such back links you can submit reconsideration request from Google Webmasters.