When do you lose your thoughts?
Excepting the mental diseases, there are two situations: when you have other thoughts that replace the first ones; when you have more important things to do than to think.
Thus, we could infer that in order to preserve some of our thoughts, we should keep them apart from other thoughts. Secondly, we must dedicate ourselves more to thinking and less to other activities.
And both of these could be taken as exigencies for the composition of thoughts, not only for their preserving.
Both of them would move the process of thinking apart from the common pattern of used for explaining its nature: as a reflection or image of reality. Because they presuppose a kind of refuge from reality: in the sphere of other thoughts or in the activity of thinking, which is farther than the reality of other human actions.
In this case, the thought cannot be appealed to come closer to real facts for reflecting them, because it would be required to it to renounce to its own nature.
It seems preferable to investigate the manner in which the real facts reach the human mind and how the interchanges and replacements of thoughts betray the processes occurred in the world of real facts.
Because the ways we compose and preserve thoughts are intended to detach from the world, but they are finally parts of the processes occurred in the world, as it is the thinker himself.