The idea in question is for a gardening tool.
Most countries provide a search engine for their patent data. Additionally there are third-party search engines for patent data. Most of these will (all the big ones do) search the text of the patents for the supplied terms. Below are some links for the most popular tools. If you are looking for US patents, I would start with Google Patents first to get a sense of what's out there. From there you can get more detailed with the USPTO's site (which has a fairly weighty searching syntax). I don't search for European assets that much, but I generally used Espacenet.
Some Unofficial (paid) sites for searching patents in addition to the sites already mentioned: