"The credit cards were used in the King of Prussia Mall," Sgt. Brady McHale told Action News on Wednesday.
One incident that happened on July 2 was caught on video.
"You see, he's moving the table so he can get close to the diners behind them," said McHale as he shared surveillance video of the act.
The video shows, in less than one minute, a man hiding his hand behind a jacket. He then grabs the victim's purse, finds the wallet, takes cards and cash. After handing the stolen items to his associate, he can be seen returning the bag to its spot.
One minute later, the pair leaves the restaurant.
"I don't even think they got lemons for their water," said McHale.
Thefts occurred four times in the past month - on July 2, 25, 26 and 27 - in Radnor Township, including in Wayne and Villanova.
Police are also looking for a woman believed to be connected to the suspects.
Police say the suspect may be driving a silver Nissan Rogue.
Radnor Township police are also in communication with Philadelphia police, looking to see if a theft from a Manayunk restaurant on June 5 is connected.