mongoose 多集合关联搜索问题,求帮助~~ - CNode技术社区

按标题、用户名(user模型)、平台名称(platform模型) 进行搜索, 怎么做关联搜索呢?

下面代码有问题,搜索不到数据:

var kw = /关键词/;
var conditions = {$or: [{"title": kw}, {"username.name": kw}, {"platname.name": kw}]};
var query = model.find( conditions ).populate({
 path: 'platname',
 select: 'name'
 }).populate({
 path: 'username',
 select: 'name'
 });
query = query.sort(sort).skip(start).limit(pagesize); 
query.exec(function (err, results) {});
var mongoose = require('mongoose'),
 Schema = mongoose.Schema,
 ObjectId = Schema.Types.ObjectId;
var timerSchema = new Schema({
 mode: Number,
 username: {type: ObjectId, ref: 'user'}, 
 platname: {type: ObjectId, ref: 'platform'},
 time: String,
 title: String,
 state: {
 type : Number,
 default : 1
 }
});		
		
// user模型
var userSchema = new Schema({
 name: {
 type: String,
 unique: true
 },
 pwd: String,
 email: {
 type: String,
 unique: true
 }
});
// platform模型
var platSchema = new Schema({
 name: {
 type: String,
 unique: true
 },
 account:{
 type: String,
 unique: true
 },
 pwd: String
});
\n```

没人作答呢