My post-post apocalyptic society (200+ years after the fall) is extremely technologically stratified, with the haves hoarding near-future technology and the have-nots making do with pre-industrial and very limited industrial tech. Enough knowledge has been lost that the fundamental concepts behind high-tech have effectively been lost, and apprenticeships begin to form around the maintenance/repair of these artifacts. Any remnants of the information age are long gone.
Enter: a trove of information similar to 4-chan, ie, a jumbled mess of political, technical, anarchic, meme-focused and borderline-edgelord content that often speaks in memetic 'code' and is not focused on teaching concepts at the tactile/applied level my people would be at (What qualities of corn would be best for ethanol? How do I repair/replace a semiconductor if I don't have scrap parts of this exact thing?).
My question: What could people with conceptual knowledge of industrial stuff (how and why a basic engine works, simple machines) and only applied knowledge of post-industrial stuff (electric stuff needs a battery, a computer can't think without the chips inside it) ...do with the information they'd find on 4-chan (defining 4-chan as it currently exists in 2018 (not the rest of the internet) and unable to be added-to afterwards) to better their lot?