Search query in url in node.js server

Question

I'm using Ovh as my hosting provider and decide to move from it's default framework in php to node.js for my website http://www.clean-weather.com

I created an server.js file with node.js server code to manage the workflow and everything is working ok until the user refresh the page when it have a search query in its url ( it appears when you are searching for forecast in the chosen city ) for example: http://www.clean-weather.com/search?lat=51.50722&lng=-0.1275

const express = require('express');
const path = require('path');

const app = express();
const port = process.env.PORT || 3000;
const DIST_DIR = path.join(__dirname, 'src/build');
const HTML_FILE = path.join(DIST_DIR, 'index.html');

const mockResponse = {
  foo: 'bar',
  bar: 'foo'
};
app.use(express.static(DIST_DIR));
app.get('/api', (req, res) => {
  res.send(mockResponse);
});
app.get('/', (req, res) => {
  res.sendFile(HTML_FILE);
});

Now I'm stuck and trying to figure out what other code I should maybe insert in that will work for that particular scenario when there is a search query.

At the end I just want to mention that in the previous scenario without node this worked fine.

Thanks in advance for every advise and help.