The reason you cannot find an easy solution to your problem is that you are trying to do something that the system intentionally does not support.
Various sources on the Internet will claim that you are either allowed light hand luggage and one (!) piece of heavy luggage, or that you are allowed "what you can carry by yourself".
Interestingly, that ...
Vienna International Airport offers porter services for departing and arriving passengers. The minimum charge is EUR 15, which covers porterage for up to five pieces of luggage. More details here: https://www.viennaairport.com/en/passengers/airport/baggage_services.
Your ticket will specify whether you may bring one bag or two bags.
If your ticket allows one bag, the bag must weigh 30kg or less. If your bag weighs more than 30kg, you will be charged extra.
If your ticket allows one bag and you bring two bags, you will be charged for the additional bag. Each bag must be less than 30kg; if either bag weighs more than 30kg,...
Assuming that you are allowed to take 2 bags according to your ticket, you will have to pay for excess baggage for any additional weight over 30Kg
According to the Qatar Airways Excess Baggage page, in the section on flying to Africa, these fees range from $USD15Kg to $USD45/Kg depending on where you start your journey.
You stated you want to take 2 x 23Kg ...