JSFiddle - React, Tailwind, and code Playground

JavaScript

sample = ["cat fat hat mat", "that the who"]
searchTerm = prompt("Testing?");

function count(sample, searchTerm) {
  var num = 0;
  for (i=0;i<sample.length;i++) {
    var current = sample[i];
    var index = current.indexOf(searchTerm);
    while (index >= 0) {
      num++;
      index = current.indexOf(searchTerm, index + 1);
    }
  }
  return num;
}

alert(count(sample, searchTerm));