The answer to your question is love.
He could not find a hint; He could not find a sign; He could not find a trail; He could not find a clue.
The kind of poem reading that the lines above represent is literal reading. There are no figures of speech here, such as metaphors, personifications, etc. which is why it's not a symbolic, figurative, or analytical reading. There is nothing to analyze here - the lines just tell the story of an eagle searching for its prey - it can't get any more literal than that.
Answer:
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