WordPress Gallery : If you want to add two, three, four or even more different galleries on a single WordPress page, you can just use some short-code like in the following examples below.
Inside square brackets  write something like this:
then for the next gallery
The letters a,b,c,d,e,f,g,h,i,j,k represent the id numbers of each uploaded image. You might have to look in the upload area to get the image’s id number/code though.
There are also a few plugins you can find in the WordPress plugin directory that will show the id if needed.