Valmiki Ramayana Sundara Kanda Sarga 12 Shloka 14
Original Shlokaइति सञ्चिन्त्य भूयोऽपि विचेतुमुपचक्रमे। भूमीगृहांश्चैत्यगृहान् गृहातिगृहकानपि।।5.12.14।।
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इति thus, सञ्चिन्त्य thinking over well, भूमीगृहान् underground cells, चैत्यगृहान् temples, गृहातिगृहकानपि homes with many doorways also, भूयोऽपि once again, विचेतुम् to search, उपचक्रमे he started.
Thinking thus, he started searching once again the basement cells, temples, homes within homes.