"Truth" is different things for different people, depending on their perspective. Thus a scientist understands "truth" differently to a priest (though they both use unconscionable means to defend their "truth turf"). On other levels a mathematician understands mathematical "truth"; an artist, artistic "truth".
Most people distinguish "truth" from an untruth. This is the most commonly held notion of "truth". This is quickly and easily elevated to a hypothesis of so-called "relative truth". One could then say that though two people or groups see things differently, what they see is legitimately "the truth" to each of them, though considered differently by the other. But this is more like point of view. Each person finds their own point of view agreeable, the others disagreeable. A third party sees that each is "right" in their own way and concludes that one man's meat is another mans poison. Therefore truth is relative.
But none of these things is about Truth. Truth must logically be mutually exclusive; two separate aspects cannot co-exist. It either is, or it is not True.
According to this view, there can be only one version of truth, that is - The Truth. How do we know that this highly prized virtue is seriously lacking on Earth? Just because we need to ask the question: "What is truth".
I read somewhere, cant recall right now, that the Buddha (or some great Buhhdist) is reputed to have said something paradoxically along the lines of: "there is only one truth on Earth: that nothing is true".
Theosophy and other oriental philosophies assert that only what is eternal and unchangeable can be True. All else is illusion. Only the causless cause, the Great Spirit, That which is but which is not, is (and exemplifies) Truth. Therefore though much can be learnt and known about the material world, it is only truth so far as it is known (derived) from The Truth. That which is derived from knowledge of the illusion is likewise illusion.
So what seems to be an obvious truth to those of us mired in illusion, such as for example that one day follows another in a linear fashion, might be a complete fiction from an eternal unchangabel point of view (past, present and future occur simultaneously - within the indivisible, timeless, causeless, boundless singularity.)
On the other hand, mortals, are supposed to be able to sense that truth, some are lucky enough to glimpse it. Usually they wish for more and in their pursuit of it make successive approximations, each hopefully nearer than the last, to The Truth (a kind of relativity, I guess) thus gaining and growing in that knowledge which carries them towards the Truth.
Or something like that...