Specialist officers from Dyfed-Powys Police, along with others from other forces, have been searching the area in and around Machynlleth since the beginning of October.
The force says the search areas identified during the course of the investigation were completed on Friday.
47-year-old Mark Bridger has been charged with murder, abduction and intending to pervert the course of justice.
He denies all the charges.
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Calming down tonight with clear spells and cooler temperatures! Setting us up for a decent start to the weekend!
Callum Williams of Wrexham pleaded guilty to causing grievous bodily harm to the woman police officer, assault and damaging property.
RSPCA says at first they thought the caller had confused the animal with a badger.