Are you speaking of things that are true that can't be proven such as mathematical conjectures, moral truths,
Physiological axioms, extensional claims.
For example, the sun will rise in the east tomorrow morning. It's not logically certain, but it's true.
In science some of what they think they've proven as fact
Since science is inductive, there is no "proof" in science. We might use the word in the colloquial sense of "enough evidence to make dissent unreasonable." But that's not what proof is.
they're always finding new evidence to change earlier analysis / hypotheses / theories.
Yeah. All science is provisional on future evidence. Which might seem flimsy to you. But nothing else humans can do, works better for understanding the physical universe.
And yes, even theories change. The atom, for example.
Hard, indivisible (hence "atom") - Democritus.
Indivisible object with a specific weight for each element - Dalton
Plum Pudding Model with discrete electrons embedded in the atom - Thompson
Planetary Model with electrons orbiting a center - Lamor, Nicholson, et al.
Planetary Model with Nucleus - Rutherford
Bohr Model with quantum states- Neils Bohr
Nucleus with protons and neutrons - Prouf
Probability waves for electons - Schroedinger
And so on...
Notice that theories, over time, don't go from wrong to right, but from wrong to more subtly wrong.