How many tweets until hashtag url twitter posts will show up?

Tweet

I feel I have been steadily working my way towards being able to be seen in a variety of hashtags. I can show up in most, without a link. However, if I was to add a link in any of them, it just disappears. What has been your experience? I always thought the amount of followers played more of a part but that just seems to be in the super well-known hashtags. I have seen someone with 17 followers and 668 tweets post in some pretty popular hashtags with a link. The link is essential to get a proper connection between the person selling and the person potentially buying. It adds another step if they have to go back to your Twitter page in order to find a link associated with what they're looking for. Any suggestions? I would like to someday actually show up in the certain hashtags but it shouldn't be this hard, especially with people with significantly less followers than me showing up there and I am not. I would think it would maybe have had something to do with the tweets with urls vs the tweets without urls amount, but the person that I have been looking into uses links in EVERY one of their twitter posts. Anyone with more information or more experience in regards to this let me know! I am still fairly new with Twitter.