You ran power from your house to your shop about a year ago The problem you are having is one of the bus legs in your shop panel box is not hot so every other 20 amp breaker is not hot on that leg?

Sounds as though you only ran a 110 volt power supply to your new shop subpanel. You need to supply 220V with a neutral and ground from your main panel to your subpanel. The 220 supply needs to come from a two pole 220V circuit breaker in your main panel. (example 50 or 100 Amp) Then, most importantly, you must use the correct size wire to carry the current. That is the wire must be sized correctly to the 220V breaker. The neutral must also be the same size as the conductors.

Once you determine how much power you need in your shop, size the supply 220v circuit breaker and wire accordingly. Check with your local building department if you are unsure or what size wire to use with what size breaker or refer to Table 310-16 in the National Electric Code.

In Australia domestic power is 240v So you have run single phase power to a three phase switchboard. To get power to those breakers you must hook the active to the busbar connected to those circuit breakers.