Śrīmad-Bhāgavatam 12.6.66
యాజ్ఞవల్క్యస్తతో బ్రహ్మంశ్ఛన్దాంస్యధిగవేషయన్ ।
గురోరవిద్యమానాని సూపతస్థేఽర్కమీశ్వరమ్ ॥ ౬౬ ॥
yājṣavalkyas tato brahmaṁś
[yaajshavalkyas tato brahmamsh]
chandāṁsy adhi gaveṣayan
[chandaamsy adhi gaveshayan]
guror avidyamānāni
[guror avidyamaanaani]
sūpatasthe ’rkam īśvaram
[soopatasthe ’rkam eeshvaram]
Word-for-word
yājṣavalkyaḥ
—
Yājṣavalkya
tataḥ
—
thereafter
brahman
—
O brāhmaṇa
chandāṁsi
—
mantras
adhi
—
additional
gaveṣayan
—
seeking out
guroḥ
—
to his spiritual master
avidyamānāni
—
not known
su-upatasthe
—
he carefully worshiped
arkam
—
the sun
īśvaram
—
the powerful controller.
Blended reading (Sanskrit + English inline)
yājṣavalkyas tato brahmaṁś
yājṣavalkyaḥ
Yājṣavalkya
tataḥ
thereafter
brahman
O brāhmaṇa
chandāṁsy adhi gaveṣayan
chandāṁsi
mantras
adhi
additional
gaveṣayan
seeking out
guror avidyamānāni
guroḥ
to his spiritual master
avidyamānāni
not known
sūpatasthe ’rkam īśvaram
su-upatasthe
he carefully worshiped
arkam
the sun
īśvaram
the powerful controller.
My dear brāhmaṇa Śaunaka, Yājṣavalkya then desired to find out new yajur-mantras unknown to even his spiritual master. With this in mind he offered attentive worship to the powerful lord of the sun.
Gauḍīya Ācāryas
Viśvanātha Cakravartī Ṭhākura
Gauḍīya
Translation
My dear brāhmaṇa Śaunaka! Yājṣavalkya, seeking mantras unknown to even his guru, began worshipping the powerful sun-god.
Adhigaveṣayan means seeking. He sought mantras which his guru Vaiśampāyana had not studied.
My note
Source: vedabase.io