Mongoose search by a property that contain multiple values

Question

Let's say I have two users in my MongoDb (user1 and user2)

      {
        UserName : "user1",
        WorkingFor : "Company1"
      }

and user2

      {
        UserName : "user2",
        WorkingFor : "Company1,Company2"
      }

now I want to search users who works for company1 using mongoose so i am using the following query :

          Users.find({WorkingFor:"Company1"}).then(foundedUsers =>{
               console.log(foundedUsers); // it will print only user1
           });

Problem : this query will return only user1 and when i modify it to :

      Users.find({WorkingFor:"Company1,Company2"}).then(foundedUsers =>{
               console.log(foundedUsers); // it will print only user2
           });

So what should I modify in my query to let it return user1 and user2 ?