Hello,
results=
Grid[{{Plot[Sin[x], {x, 1, 5}]}, {Plot[Cos[x], {x, 1, 6}]}},
Frame -> All, FrameStyle -> Directive[Red, Dotted]]
will produce this 
But export this figure to pdf will lose the left and right frames
Export["C:\\Users\\hello\\Downloads\\delete.pdf", results]
