MongoDB can't index large keys - unable to perform full-text search

I am developing a MEAN web app for books. I am trying to perform full-text search on my ebooks schema (I am using mongoose for the schemas):

var eBookSchema = mongoose.Schema({
    title: {
        type: String,
    },
    path: {
        type: String,
        required: '{PATH} is required'
    },
    chapters: {
        type: [String],
        required: '{PATH} is required',
        text : true
    },
    uploaderID: {
        type: ObjectId,
        ref: 'User',
        required: '{PATH} is required'
    },
    uploaded: {
        type: Date,
        default: Date.now
    }
});

To perform the full-text search, I need a text index, as specified in the Mongo Docs. The problem is that the chapters contents are bigger than MongoDB's index key limit, which is 1024 bytes (docs). That's why I always get the following error when trying to insert a document:

Btree::insert: key too large to index

The document is inserted, but no index is created, and I cannot perform full-text search. I am open to any ideas. Can I define my schema in a different way, that will work with indexes? Or should I use some search server, like Solr or ElasticSearch?