Valmiki Ramayana Yuddha Kanda Sarga 4 Shloka 12
Original Shlokaनिम्नेषु वनदुर्गेषु वनेषु च वनौकसः । अभिप्लुत्याभिपश्येयुः परेषां निहितं बलम् ।।6.4.12।।
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वनौकसः inhabitants of woods, vanaras, निम्नेषु in low lying lands, वनदुर्गेषु in inaccessible water sources, वनेषु च and in forests, अभिप्लुत्य by leaping up to sky परेषाम् beyond sight, निहितम् placed, बलम् army, अभिपश्येयुः should even look for
"O Vanaras You should even look for (the rakshasas) in the low lying lands, in inaccessible water sources, in forests and also beyond sight leaping up to the sky".