"Drawing Tools" doesn't have anything for drawing arcs.
You can however programmatically draw arcs:
Graphics[Circle[{0, 0}, 1, {Pi/6, 3 Pi/4}]]
This would require finding the end points and doing some calculations depending on how you want the arcs to look.
For more complicated graphics editing, I often export to a vector graphics format and use a program like inkscape or another vector graphics editor.
