Mongoose: How to findById when the query is not complete - node.js

Question

I am building a search query where it will find a database object by its ID even while the user is typing.
ordersRouter.route('/searchorder/:term')
.get(function(req, res){
term = req.params.term;
console.log(term);
Orders.findById(term)
.populate({ path: 'userPurchased products.product', select: '-username -password' })
.exec(function(err, orders){
if (err) throw err;
res.json([orders]);
});
});
The problem here is that when the term does not exactly the same as the ID, it will return nothing. How can I return IDs with partial term?
EDIT: My order model schema
var orderSchema = new Schema({
orderId: { type: String },
userPurchased: { type: Schema.Types.ObjectId, ref: 'users' },
products: [
{
product: { type: Schema.Types.ObjectId, ref: 'products' },
size: { type: String, required: true },
quantity: { type: Number, required: true },
subTotal: { type: Number, required: true }
}
],
totalQuantity: { type: Number },
totalPrice: { type: Number },
modeOfPayment: { type: String },
shippingAd: { type: String },
refNumber: { type: String },
isDone: { type: Boolean, default: false },
orderStatus: { type: String, default: 'Pending' },
dateOrdered: { type: Date, default: Date.now() },
fromNow: { type: String }
});

Answer 1

You can run your query using regex i.e. create a regular expression object from the string using the RegExp constructor then run the query as:
ordersRouter.route('/searchorder/:term')
.get(function(req, res){
term = req.params.term;
console.log(term);
Orders.find({'orderId': new RegExp(term)})
.populate({
path: 'userPurchased products.product',
select: '-username -password'
})
.exec(function(err, orders){
if (err) throw err;
res.json(orders);
});
});