Try to be more creative with your tags. I get that your item is a tutu, but there are other words to describe them (skirt, costume, outfit, dress up).
For this item below, 12 of your 13 tags have 'tutu' in them.
https://www.etsy.com/listing/465701744/witch-tutu-custome-witch-halloween-tutu?ref=shop_home_active_...By putting 'tutu' in one tag, you're already relevant for searches of 'tutu'. Change some of them up. Make 'halloween tutu' into 'halloween costume' and 'elastic tutu' into 'elastic skirt'.
"custom baby gift" "dress up outfit" "girls birthday skirt"
Just think about what a variety of customers might search for. Not everyone may say 'tutu'.
Also be careful of copyright infringement. Saying DC Comic or DC Superhero or Wonder Woman, is technically not allowed per copyright law (unless you're selling a DC comic book or something originally made by DC comics that you're re-selling). Not trying to be a jerk, just making you aware.