Google Trends works as a simple version of Google's analytics tools. Its primary function is to gather and compare the searches that people make all over the world. The data is then broken down into different categories. It can also be viewed through different filters. The only information you need to use Google Trends are the keywords that you incorporate into your own marketing strategy.
To make the keyword research relevant, you need to search for both your ideal keywords and any keywords that are close to your keywords. To do this, you can track the keywords that are already used in your SEO marketing campaign. If you can't think of more than a few alternative keywords, you may want to try using services like Keyword Tool. This service will suggest several different terms that will near to your original keyword. Using more thana couple of search terms will help your research be more inclusive and therefore more valuable.