If its useful, its gone. First rule of scavenging my boy, if its useful, it is gone. Oil based fuels go stale, biofuels break down - their degradable nature is half of why we started using them after all - doesn't poison the environment. As much. Drugs in a form that can be administered - gone. Food? Even military MREs need to kept in a cool place to last more than two years. Rubber gloves are hard to find too.
So, what is the point of searching? Because anything else tends to be worth it. Nano-vac isn't organic, so it doesn't rot. Neither do the CAD files for manufacturing, and the whole point of bio-plastic is that you can make it with the right plant materials, rather than drill under the gulf of Mexico.
You don't want the stuff, you want the things that make the stuff. That is where the real prosperity is. A bad scav looks for guns, a good one looks for three inch flange valves. Guns are a rare find, and of negotiable use. Anyone who is trying to irrigate crops, produce fuel, run a chemical factory, purify water - they're going to need valves and pipe.
Copper wire is great - send signals, tie up plant creepers, bale hay, use in certain chemical processing.
The best of us don't need to go looking for stuff. We know alternate uses for things on hand and just sell it. You would be surprised how many people dismiss broken glass as just refuse, rather than impromptu wall spikes or a precursor to optical cables, or even just potential jars for preserves. No one is reinventing the wheel here, so raw materials are still a thing of value.
So I'll tell you what - you are going to go into that block over there. I'll give you three days to find enough stuff to pay for a five day stay in a town. You do so, you stay on with the group. Anything beyond six days, you get the excess. Fail, and we leave you here with the reanimates.