Lol, sounds like a bit of work!
Firstly, SEO stands for search engine optimisation. Its basic about making your site search engine friendly! Theres a good guide in the sellers handbook for all aspects of tagging and seo, which go hand in hand with relevancy. To optimise your listings you need keywords that are 'relevant' to your items. Also, the more you use those keywords in your listings the more relevant your items will be in a search.
As a good starting point, search for a similar item, what ever comes up first is the most relevant to that search term. Check out their tags and item titles, descriptions for some ideas on what you should be putting in yours. Make sure you read the Seller Handbook articles too ok.
Keep working on making things better and you'll start to see improvements.
Hope that helps you
Crystal
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