How to get specific element inside of element stored in variable?

I am looking for way to select element inside of already located element in variable. For example I have selected a container:

let productAttachedFilesModal = document.getElementById('modal_more_information');

I know, that inside are array of a elements, which I want to select as well. Which method should I use? in jQuery there are method find(). So I need the analog for JS.
Or I need to use DOM method again? Like this:

let listOfLinks= document.getElementById('modal_more_information > a');