Every effort made by student working with one on run (2,5,8)

I believe the answer is:

no stone unturned

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'every effort made' is the definition.
I can't judge whether this defines the answer.

'student working with one on run' is the wordplay.
'working with' indicates an anagram (working with the letters).
'one'+'on'+'run'='oneonrun'
'student' anagrammed with 'oneonrun' gives 'NO STONE UNTURNED'.

'by' acts as a link.

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I've seen this clue in The Independent.

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