Those countries are all very different with very different interests in their respective regions. China doesn't care about Ukraine, Russia doesn't care about Taiwan, and both were very muted in their reaction to the attacks on Iran.
The major thing they have in common is not respecting American trade embargoes against themselves, which, of course they don't.
They had muted (visible) reaction because they could do little about it.
Their muted reaction is a tacit approval.