Yuktidīpikā (earlier than Vācaspati) also cites the verse laghūni sūcitārthāni… (Wezler/Motegi edtition 4.2-3).

Also:  āha | atha sūtramiti kasmāt | ucyate | sūcanāt sūtram | sūcayati tāṃstānarthaviśeṣāniti sūtram | … atha vā bhikṣorupasaṃhṛtabahiṣkaraṇāntaḥkaraṇasya teṣu teṣvatīndriyeṣvapi pradhānādiṣvartheṣu buddhiṃ sūcayatīti sūtram | (Yuktidīpikā Wezler/Motegi edtition 3.20-21, 25-26).

On May 14, 2021, at 11:08 AM, Uskokov, Aleksandar via INDOLOGY <indology@list.indology.info> wrote:

laghūni sūcitārthāni

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