If i was travelling from Harare to Johannesburg by air on a round trip ticket then return road Is it possible fly again in the direction using same ticket?

It is not possible to use a round-trip ticket for one flight in one direction and then fly back in the other direction using the same ticket. A round-trip ticket is valid for one round-trip journey, between the cities specified on the ticket. If the ticket is used partially (e.g., one flight in the required direction and then not returning), the remaining unused portion of the ticket becomes void.

If you want to fly from Johannesburg back to Harare after your initial flight from Harare to Johannesburg, you would need to purchase a separate one-way ticket or a new round-trip ticket. Please note that airline policies and ticket conditions can vary, so it's always recommended to consult with the airline or travel agency for specific details and restrictions regarding ticket usage and changes.