Valmiki Ramayana Aranya Kanda Sarga 69 Shloka 24
Original Shlokaतयोरन्वेषतोरेवं सर्वं तद्वनमोजसा। संजज्ञे विपुलः शब्दो प्रभञ्जन्निव तद्वनम्।।3.69.24।।
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तयोः both, एवम् in that manner, ओजसा with strength, सर्वम् all over, तत् वनम् that forest, अन्वेषतोः while both were searching, तत् वनम् that forest, प्रभञ्जन्निव as if shattering, विपुलः very big, शब्दः sound, संजज्ञे broke out.
As both the brothers with great prowess were searching for Sita all over, a huge sound exploded as if shattering the forest.