If you want to know how people find your website purely through google search, you can make use of Google Analytics.

 First, you login to your Google Analytics account. Then you goto the Traffic Sources on the left menu. Choose Search Engines. The main area will show you a list of all the search engines that are sending you traffic. If you click on Google and you will see a keyword list of all the keywords used to find your site via Google.

If you add keywords through your Google Adwords, you may want to combine Google analytics and Google Adwords to give you the best value for money. Below is a Google video that shows you how to do it.

In general, high bounce rate means that your site is not interesting to the visitors. However, for some cases, high bounce rate may not mean your site is not interesting. There are several other reasons for high bounce rate, for example,

- A site has a splash page intro, with only the words 'click here' on it. - A visitor is looking for sites selling widgets in order to find the best place to buy one online. They enter on the product page from a search query, make a note of the site and leave.

- The visitor has an informational query which is immediately answered by your landing page.

When we use Google Adwords PPC to increase traffic and online sales, one often looks at the total clicks and click through rate (CTR). While these metrics do reflect the amount of traffic to your site, what is more important for ecommerce sites is how much of these clicks really translate to sales. This is measured by the conversion rate. Conversion rate alone is not enough to measure the true effectiveness of your Google Adwords campaign. While higher conversion rate does indicate higher online sales, the effectiveness of your Google Adwords campaign is also measured by ROI which is defined as

ROI = Profit per conversion/cost of conversion

Higher conversion rate, coupled with higher ROI means a successful campaign. You can learn a lot about Google Adwords from the following series of Google Adwords Educational Videos from Google.