JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://rawgit.com/olivernn/lunr.js/v2.0.0-alpha.5/lunr.js" />

<div>Results:</div>
<ul id="result-list"></ul>

JavaScript

const data = [{"type":"exhibitors","id":1,"name":"chêne et âtre"},{"type":"exhibitors","id":2,"name":"Événement"},{"type":"exhibitors","id":3,"name":"Général"},{"type":"exhibitors","id":4,"name":"3D SYSTEMS LAYERWISE"},{"type":"exhibitors","id":5,"name":"3V FASTENERS"},{"type":"exhibitors","id":6,"name":"40 - 30"},{"type":"exhibitors","id":7,"name":"4DCONCEPT"},{"type":"exhibitors","id":8,"name":"A&P INTERNATIONAL SERVICES"},{"type":"exhibitors","id":9,"name":"A&T AEROSPACE"},{"type":"exhibitors","id":10,"name":"A.E. PETSCHE COMPANY"},{"type":"exhibitors","id":11,"name":"A.I.A.D AND MOD ITALY"}];


lunrIdx = lunr(function() {
  this.ref('id');
  this.field('name');

  this.metadataWhitelist = ['position'];

  data.forEach(function (doc) {
    this.add(doc)
  }, this);
});


// OK
// const userInput = 'SYSTEM';
//const userInput = 'général';

// KO
const userInput = 'genéral';

let results = lunrIdx.search('*'+userInput+'*');


// Display results
let divCounter = document.createElement('div');
divCounter.textContent = `${results.length} results`;
document.body.appendChild(divCounter);

let ul = document.createElement('ul');
document.body.appendChild(ul);

results.forEach((result) => {
	let li = document.createElement('li');
  li.textContent = data.filter((dataEntry) => dataEntry.id === parseInt(result.ref, 10))[0].name
  ul.appendChild(li);
});