async.map

async.map.js

async function asyncFunction(name) {
    await collection.find({
        "name":  new RegExp(name, 'i')
    }, (err, res) => {
        if(err)
            console.log("Error:",err);
        else {
            async.map(res, (item, callback)=>{
                anotherCollection.findById(item.id, (err, res)=>{
                    if(err)
                        return callback(err);
                    else{
                        let toRet={};
                        // Add Business Logic
                        return callback(null, toRet);
                    }   
                })
            }, (err, res)=>{
                if(err)
                    console.log("Error:",err);
                else
                    console.log("Success:",res);;
            })
        }
    })
}