Re: How to know keyword Search volume[ Edited ]
August 2013 - last edited August 2013
It all can be done with the Keyword-Planner tool in AdWords: https://adwords.google.com/o/KeywordTool
More info about it: http://adwords.blogspot.ch/2013/05/introducing-keyword-planner-combining.html
Re: How to know keyword Search volume
You can do keyword research through Google Adwords keyword planner tool recently replaced with Keyword Tool. You can get average monthly search and historical data for your keywords.
I suggest you to refer this link - https://support.google.com/adwords/answer/3141229