Because both Iran and Russia are major oil producers, and the Iran war is disrupting oil supply from Iran, which allows Russia to sell more oil and at a higher price, at a time when they desperately needed to do so.

Russia's economy is almost entirely dependent on exporting oil, they don't really have much else going for them economically, and they started an illegal invasion war (that they are embarrassingly losing) while actively committing a genocide against the Ukranian people, so their oil is heavily sanctioned and can't be sold to most of the world. What little they could sell, they had to sell cheap.

The Iran war is a gift to Russia, saving them from economic collapse. The oil supply is so disrupted that sanctions are now being lifted on Russia, despite the fact that they are still genociding Ukrainians.

You're so concerned about civilians, where is your outrage for the Ukrainian civilians that are targeted victims of Russia's illegal war and genocide?