przelewać z pustego w próżne

Etymology
lit. 'to pour from [an] empty [container] to [an] empty [one]'. Compare 🇨🇬, 🇨🇬, and 🇨🇬.

Verb

 * 1)  to blow hot air, to waffle
 * 2)  to chase one's tail, to mill the wind, to plow the sands
 * 1)  to chase one's tail, to mill the wind, to plow the sands