Hello! :) I wish I had better advice for you, but I honestly don’t know how I get my writings seen. It took awhile, and a lot of practice, daily writing uploads, and tons and tons of writing on my part.
It also helps to do collabs with other writing blogs, to connect with other writing blogs by starting conversations with their owners about writing, etc.
Delve into the writing part of tumblr as best you can and that should help.
I really don’t know very much about how to get noticed on tumblr, though, so I’m sorry that wasn’t very helpful. :o
xo