How can we know that a particular keyword has been searched and for how many times in google or other search engines per month or ? Is there any free tool or any trick to search in google or other tool ?
There is not any such tool for Google which is showing specific figures. But you can use http://inventory.overture.com or http://www.keywordtracker.com for keyword research.
inventory overture is the best tool to get those things... but you must also know the better market... there are various thing which you must keep in mind before any decision to take a keyword.
The Wordtracker and the Overture tools are alright although their figures are not 100% exact, but they provide some nice general info about the keywords.
if your Targted SEs Is Google Try This one... https://adwords.google.com/select/KeywordToolExternal It shows No. of Competition & Search Volume of a Certain Keyword Hope It Helps.