test1/public/drupal-8.3.1/modules/user_import/js/main.js

function searchFunc() {
    var input, filter, table, tr, td, i;
    input = document.getElementById("filter-input");
    filter = input.value.toLowerCase();
    console.log(filter);

    table = document.getElementsByTagName("tbody")[0];
    console.log(table);
    tablerow = table.getElementsByTagName("tr");
    console.log(tablerow);
    // Loop through all table rows, and hide those who don't match the search query
    for (i = 0; i < tablerow.length; i++) {
        td = tablerow[i].getElementsByTagName("td")[2];
        console.log(td);
        label = td.getElementsByTagName("label")[0].innerText;
        if (label) {
            if (label.toLowerCase().indexOf(filter) > -1) {
                tablerow[i].style.display = "";
            } else {
                tablerow[i].style.display = "none";
            }
        }
    }
}