Valmiki Ramayana Aranya Kanda Sarga 61 Shloka 20
Original Shlokaतौ वनानि गिरींश्चैव सरितश्च सरांसि च।।3.61.20।। निखिलेन विचिन्वानौ सीतां दशरथात्मजौ।
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तौ दशरथात्मजौ those two sons of Dasaratha, वनानि forests, गिरीन् चैव and the mountains, सरितश्च and the rivers, सरांसि च and the ponds, निखिलेन entirly, सीताम् for Sita, विचिन्वानौ while they searched.
The two sons of Dasaratha went on searching for Sita in forests, mountains, rivers, ponds everywhere.