How can i access $refs that is a children of another $refs?

How can i use refs in my vue component (preferably in a loop) to manipulate multiple dom elements in my template? Let’s say for example that i want to apply an animation with GSAP on every <p ref="pre"> in a function. How would i do that? Like i would i access them in mounted as an array or something? Current code will only apply for the first element right?

I have a simple page to use vue.js 2.0, I need to wire the button’s click event to call the search function, but I got the following error in console when the page load: