JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container"></div>

JavaScript

var keywords = [ 'An Example', 'Test'];
var str = "Lorem ipsum dolor sit amet, consetetur sadipscing elitr\n"+
    "Test: Lorem ipsum dolor sit amet, consetetur sadipscing elitr\n"+
    "This is An Example Lorem ipsum dolor sit amet, consetetur sadipscing elitr\n"+
    "An Example Lorem ipsum dolor sit amet, consetetur sadipscing elitr";

var result = [];
str.split('\n').forEach(function(pg) {
    console.log(pg);
    var any = false;
    for (var idx in keywords) {
        var keyword = keywords[idx];
        if (pg.indexOf(keyword) == 0) {
            result.push("<span style='font-weight:bold'>" + keyword + "</span>");
            var stripped = pg.substr(keyword.length);
            if (stripped.indexOf(": ") == 0)
                stripped = stripped.substr(2);
            result.push(stripped);
            any = true;
        }
    }    
    if (!any) result.push(pg);
});
console.log(result);
function append(text) {
    $("#container").append($("<p>").html(text));
}
result.forEach(append);