There are several ways to understand what are the keywords that people are using when searching for the information online. One of the most popular sources for this data is Google Keyword Planner. Unfortunately, it is an instrument tailored to people that create AdWords campaigns and in most cases will show next to none long tail keywords. The great source of the long tail keywords is Google search suggest. Search suggestions are generated by the algorithm that aims to produce the most relevant suggestions for a user query. Although it is possible to type keywords manually into Google search box and try to copy phrases that show up in the autocomplete, it is much easier and faster to get these long tail keywords using Longtail Keywords Finder Tool. This tool will take your search term and query Google along with different letters and numbers. It will keep generating long tail keyword suggestions and let you export them as well.
Longtail Keywords Finder Tool