mognoose在多列中使用正则表达式进行搜索

我有一个mongoose模型,模式定义为 -

var campusNotesSchema = mongoose.Schema({
    noteId:{type:String, unique:true, default: uuid.v4()},
    title: {type:String, required:'{PATH} is required!'},
    uploader:{type:String,required:'{PATH} is required!'},
    department:{type:String},
    college:{type:String},
    author:{type:String,required:'{PATH} is required!'},
    actualFileName: [String],
    storedFileName: [String],
    subject: {type:String},
    description: {type:String},
    details: {type:String},
    date: {type:Date, default: Date},
    tags: [String]
});

而模型定义为 -

var Campusnotes = mongoose.model('Campusnotes', campusNotesSchema);

现在我想从请求对象参数中搜索标题,标签,描述字段

if(req.query.searchText){        
    Campusnotes.find({title:new RegExp(searchText,'i'),description:new RegExp(searchText,'i')}).exec(function(err, collection) {
        res.send(collection);
    })
}

现在我如何确保在标题或描述中找到该术语的任何结果也包括在内,而不仅仅包括两者中的结果.另外,我如何在tags数组中搜索匹配的字符串