JSFiddle - React, Tailwind, and code Playground

JavaScript

var foo = {
    "hello[35]": 100,
    "goodbye[45]": 42,
    "hellohello[36]": 67,
    "hhello[78]": 33
};
var query = "hello";
for (var key in foo) {
    if (key.indexOf(query+"[") == 0) document.write(foo[key]);
}