if they are brazing rods (usually a copper alloy) then they are different to silver solder rods (usually 50% silver+) but they will work in the same way and with the same theory. The graze will flow to wherever there is flux and work using a capillary action
And a different flux due the higher temperatures. 'Silver solder' covers a lot of ground (and very little silver to 60 odd %) and is actually brazing albeit at lower temps than 'proper brazing'