विजिज्ञास्यतया यच्च वेदान्तेषु मुमुक्षुभिः ।समर्थ्यतेऽतियत्नेन तद्ब्रह्मेत्यवधारय ॥ ३४ ॥
In plain words
That which earnest seekers of freedom strive with all their might to know through the Upanishads as the supreme object of inquiry—know with certainty that this is Brahman.
Close to the Sanskrit
And that which is sought to be known with supreme effort by seekers of liberation within the Vedāntas—ascertain that to be Brahman.