Why it is hard to seo for shopify？

I have tried and still doing SEO for a ecommerce shopify and its taking years to rank what factors should i focus on 2 to 3rd tier url.

Interested to hear more on this topic as I'm not sure. I've never done shopify but always open to different ideas. Are you trying to compete for difficult keywords? For example "t-shirt" would be tough. But "biker t-shirt for babies" would probably be easier. but also another tricky way is that to open multiple shops in MoreLogin to get traffic.

whats your main kw?