How to optimize text indexing and searching in DocumentDB?

Question

I have a Node.Js web app hosted in DEV and PROD environments.

There I'm calling an API to get user/s upon text search by using index.This user collection is having more than 50,000 records.

but unfortunately Document DB is not supported for Indexes type of 'text'.

Is there any other way to achieve the same behavior(index type of text or any option) without having performance issue in Document DB?

Please refer to the below code.

const findUserByName = async (req, res, next) => {
  let users;
  const where = {};
  try {
    const { name } = req.body;
    const Users = UserModel(req.tenantId);
    if (name){
      where['$text'] = {$search: new RegExp(`\"${name}\"`, "i")}
    }
    users = await Users.find(where, {name : 1, _id : 1, code : 1, active : 1});
    return res.send(new ApiResponse(users));
  }catch (e) {
    return next(new InternalServerErrorException(e.message, e));
  }
}

User Model

 const UserSchema = new Schema({
        id: {
            type: Schema.Types.String,
        },
        name: {
            type: Schema.Types.String,
        },
        code: {
            type: Schema.Types.String,
        },
    });
        UserSchema.index({name: 1});
        UserSchema.index({name: 'text', code : 'text'});