• nāmāni — names
  Plural of nāman. Kṛṣṇa's names are countless — sahasra-nāma is only a glimpse. Gauḻīyas teach that nāma is non-different from nāmī (Padma Purāṇa); each name carries the full Person. To know His names is partial vision; to chant them is full union.
• rūpāṇi — forms
  Plural of rūpa. Bhagavān has unlimited forms — Nārāyaṇa, Vāsudeva, Saṅkarṣaṇa, Rāma, Nṛsiṁha, and Kṛṣṇa (svayaṁ-rūpa). Garga hints at the avatāra-mālā without unfurling it; Nanda needs the hint, not the catalog.
• guṇa-karma-anurūpāṇi — according to His attributes and activities
  Guṇa (quality) + karma (act) + anurūpa (in accordance). Each name and form expresses a particular pastime — names and līlās are mutually generative, never arbitrary.
• veda — know
  Perfect of √vid — 'I have come to know.' Garga modestly claims jñāna of Kṛṣṇa's nāma-rūpa, distinguishing himself from janāḥ (ordinary people). Gauḻīya paramparā depends on such recognition: tattva-darśin teachers.
• na u janāḥ — not ordinary persons
  Na (not) + u (emphatic) + janāḥ (people). Garga is not boasting; he is locating the gopas' bewilderment inside a wider human pattern. Only Vaiṣṇavas in paramparā know Kṛṣṇa's nāma-rūpa-līlā fully.

• Romapada Sw SB 10-26-18-20 - Nature of Lords Names and Activities - 2020-04-15 Naperville
  His Holiness Romapada Swami· 2020-04-15· English

A father might know his son's pet names — the ones used by the grandmother, the brother, the teacher — while strangers know only the legal name. Garga is telling Nanda: this child has more names than the village will ever sing, and I know them; do not be surprised when the names start to surface.