Search multiple fields with easy search

Hello, first post here and it’s probably a simple issue but any help would be appreciated.

I’m using easy search to search over a collection, and each entry in this collection has a few fields I’d like users to be able to search by (the title or author of a book, for example). However, currently I can only search by title, despite looking like I’ve set it up correctly. Here’s what I have:

`Books = new Mongo.Collection('books');

BooksIndex = new EasySearch.Index({
    collection: Books,
    fields: ['isbn', 'title', 'author'],
    engine: new EasySearch.Minimongo()
    booksIndex: () => BooksIndex

And then a simple search page:

<template name="buySearch">
    <div class="container">
        <div class="home">
    {{> EasySearch.Input index=booksIndex}}

        {{#EasySearch.Each index=booksIndex}}
            {{> bookItem}}

    {{> EasySearch.LoadMore index=booksIndex}}

    {{#EasySearch.IfNoResults index=booksIndex}}
        <div class="no-results">No results found!</div>

Sorry for the long post. Any idea why the search input is currently only showing results if I input the book title? Nothing for isbn or author. Thanks in advance for any help or suggestions!