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Ah then, that's a bigger question. You're using an excellent tool, Yoast. Stick with it. It could be it isn't configured properly, you're in a highly competitive market, or there are other issues getting in the way of your advancement. After a quick look at your site, three things jump out: structure, speed and links. (1) Your site structure is extremely flat, meaning your link equity is getting disbursed across almost every page on the site. You should aim for a short, fat pyramid structure with top level pages being your most important. You're also inconsistenly using www and non-www links internally to the site. That's contributing to the next problem and diluting your link equity because of unnecessary redirects. (2) Your site is slow. It ranks very poorly using Google's speed test. Speed is an important ranking factor these days. (3) You seem to have a lot of questionable incoming links to the site. You might need to do a link cleanup. I'd recommend a complete SEO audit and suggest you reference this extremely helpful post from Moz in order to understand the types of things you should be looking for.