Getting multiple Arraylists from multiple Room DAO

Question

Previously I am using Sqlite database with SqliteHelper class. As Room is much easier , I started to migrate that to AndroidX Room.

In sqlite database I get data as follows and process thereafter

  ArrayList<DCRData> dcrData = new DataLoader(mCon).getDCRData(Year,Month);
  ArrayList<ExpensesData> expensesData = new DataLoader(mCon).getExpensesData(Year,Month);
  ArrayList<MileageData> mileage = new DataLoader(mCon).getFilteredMileageData(Year,Month);

I used to interconnect those Arraylists and generate the data I want. The problem I have is , how can I do the same in Room? By using observer and LiveData, I am getting those data in different time. Can I get all thses mutliple data streams as above ?

Do I need to use the following code multiple times?

   LiveData<List<ItineraryData>> DayItinerary = new ItineraryRepo(mCon).getDayItinerary(Date, Month,Year);

    DayItinerary.observe((LifecycleOwner) mContext, new Observer<List<ItineraryData>>() {
        @Override
        public void onChanged(List<ItineraryData> models) {

   
        }
    });

Thank you

(I am a newbie to Androidx Room)