Bricks, Masonry, Asphalt and Concrete - Adherring 1" Pavers over Concrete Driveway

Our driveway is concrete and appears to have been painted long ago. (We just moved in.) They put 1" thick pavers, 3 different shapes, over the concrete. The pavers along the edges appear to have been set in a thinset mortar. The field is just layed over the concrete. Some of the edge pavers are loose. it appears that the thinset stuck to the pavers real well but did not make a good bond to the painted concrete. It also appears that there may have been an imprinted brick look on the concrete. My question is: What type of adhesive/motar should I use? Is thinset the best choice or should I use one of the caulking cartridge type of mastics. Thanks for any help.