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To add to what Kyle said, the reason you are seeing these statistics is because you have virtually no inbound links that point to your domain. Without inbound links, web crawlers have no way of finding your site. Search Engines such as Google also use links to determine how popular a site is. To put it (over)simply, the more links that point to your site, the better you are likely to do in search results. The best way to improve your domain metrics like Domain Authority (and even PageRank) is to start building links. But first, I'd start by reading the Beginners Guide to SEO. Building high quality links is difficult and rewarding, but almost nothing is more rewarding for SEO. Hope this helps. Best of luck with your SEO!