Collocations for sift - verb

carefully
out
They will try to sift out the winners and the losers.

for
He's mentally sifting for truths.

through
They spent days carefully sifting through the evidence.

spend hours sifting through sth, spend time sifting through sth
I spent hours sifting through those heavy art books.

Sift is used with these nouns as the object:
flour