Riverina Police District officers searched 3120 people during 2018, including more than 500 children, but found nothing in 90 per cent of cases.
'Objects' were found in about 9.2 per cent of juvenile searches and 10.1 per cent of adult searches in Riverina Police District, which is has its head office in Wagga Police Station.
Across NSW, an average of 12 per cent of police searches came up with relevant items.
More than 16 per cent of adults and children searched in the Riverina were recorded as having being Aboriginal or Torres Strait Islander.
The total numbers of both juvenile and adult searches declined in the Riverina between 2017 and 2018.
A NSW Police Force spokesperson said searches were "a vital detection tool and are often necessary to find and seize" illegal drugs and weapons.
"Any time a police officer executes their search powers, they must hold a reasonable suspicion as required by the Law Enforcement (Powers and Responsibilities) Act," the spokesperson said.
"A search cannot be conducted if this criteria is not met.
"There are additional safeguards for children and vulnerable people with which police must comply. Officers are trained to deal with the public in a respectful and empathetic manner, and to be aware of potential cultural sensitivities."
The police search numbers were contained in a Bureau of Crime Statistics and Research report.
The Murray River Police District, with its head office in Albury, carried out fewer searches of children than in the Riverina, with 402 incidents in 2018.
Murray River Police District also recorded about 800 fewer searches of adults compared to the Riverina.
Murrumbidgee Police District, headquartered in Griffith, saw a peak of 120 searches of children and 2400 searches of adults over 2017 and 2018.
The NSW Police Force spokesperson said "proactive policing strategies' such as searches and move-on directions "have been proven to significantly drive down crime, particularly in relation to property crimes such as break-ins, motor vehicle theft, robbery, armed robbery, thefts including shoplifting and street offences".
"Recent independent research conducted by the Bureau of Crime Statistics and Research stated that increasing the number of police searches and move-on directions reduces crime," the spokesperson said.