Best image scanning software?

Is there some kind of software out there that can actually "read" an image? Something along the lines of ABBYY FineReader, but for drawings instead of just plain text.
Basically, I need something that can strip away everything except the actual lines. Every time I scan these things, the background comes up all yellowed and filthy—it’s a mess. I just need a way to clean that junk out.

P.S. We aren't talking about photography here. I'm looking at technical stuff—like a cross-section of a bolt, an electrical schematic, or a cutout of a fuse. It's strictly line work.

Come on, you’ve gotta be kidding me—is there seriously nobody here who actually knows anything? 😢😢

You didn't mention which file format you actually need...
If we're talking bolts and schematics, I'm guessing you need it in Cisco

http://www.img2cad.com/

I think there are plenty of others out there... just type "jpg or pdf to dwg or Cisco" into Google and see...