Node JS and Mongoose How to get data from 2 collections? - node.js

Question

I need to get all docs from service collection and it's showing all records when i console content. In content collection there is field mids which is media id and all images are going to media collection. I need to get media url for specific service. But when i console content.mids it returns undefined .Do i need to change in query?
Code is attached for your reference.
// Controller
services: (req, res) => {
Posts.find({content_type:'service'}).then(function(content) {
console.log(content); //right
console.log(content.m_ids); //showing undefined
Media.findById(content.m_ids).then(media => {
res.render('default/services', {content: content, reqUrl: req.url});
});
})
}
Services Model
const mongoose = require('mongoose');
const Schema = mongoose.Schema;
const Schema = new Schema({
content_type: {
type: String,
required: true,
maxlength:20
},
content_title: {
type: String,
required: true,
max:100
},
content_url: {
type: String,
required: true,
maxlength:200
},
content_description: {
type: String,
required: true,
},
content_full_description: {
type: String,
required: false,
},
pt_ids: {
type: String,
required: false,
},
pc_ids: {
type: String,
required: false,
},
m_ids: {
type: String,
required: false,
},
created_by_user_id: {
type: String,
default: 1,
},
created_on: {
type: Date,
default: Date.now
},
updated_on: {
type: Date,
default: Date.now
},
post_icon_svg: {
type: String,
required: false,
}
});
module.exports = {Posts: mongoose.model('content_data', PostsSchema )};
// Media Model
const mongoose = require('mongoose');
const Schema = mongoose.Schema;
const MediaSchema = new Schema({
media_name: {
type: String,
required: true
},
media_title: {
type: String,
required: true
},
media_alt: {
type: String,
required: true
},
media_description: {
type: String,
required: false
},
media_url: {
type: String,
required: true,
unique: true
},
created_by_user_id: {
type: String,
default: 1,
},
created_on: {
type: Date,
default: Date.now
},
updated_on: {
type: Date,
default: Date.now
}
});
module.exports = {Media: mongoose.model('media', MediaSchema )};