The ARA San Juan went missing on 15 November, while on patrol in the South Atlantic with 44 crew on board.
On Thursday night, Argentinian authorities abandoned the rescue attempt but said the search for the submarine would continue.
On Friday, navy spokesman Enrique Balbi, said: "Concretely, there were six contacts [items discovered on the ocean floor by sonar searches] in the last few days that have been positioned, of which two have been completely discarded.
"We have to count on the submersible vehicle who have to do a visual inspection, to confirm or not if those contacts are something metallic that might suggest they are the submarine."
Hope was fading for the crew before the announcement to call off the rescue mission, as they only had enough oxygen for around two weeks.
The navy has said the vessel's captain reported water had entered the snorkel and caused one of the submarine's batteries to short circuit.
The captain later communicated via satellite phone that the problem had been contained.
Hours later, an explosion was detected near the time and place the sub was last heard from.
Aircraft have flown some 557,000 nautical miles, while ships have searched more than a million nautical miles in the hunt for the submarine.