From Longman Dictionary of Contemporary Englishpick through something phrasal verbLOOK FORto search through a pile of things to find things that you want Police are still picking through the rubble looking for clues to the cause of the explosion. → pick→ See Verb table
Examples from the Corpus
pick through • Another edges his way towards him ... picking through mines and tripwires.• Children pick through piles of spoiled food in the alleys outside.• A man and a woman pick through the filth while cattle forage.• Gary is silent again, and eats carefully, his huge hands delicately picking through the food, his head clamped downwards.• I loved to pick through trash piles and collect empty bottles, tin cans with Pretty labels, and discarded magazines.• They pick through trash, poke through mail and tap into sophisticated computer databases in search of the elusive money trail. 