DeJa vu is the reult of our brains seeking patterns to associate. Our minds work as story writing machines creating narratives that often include details not actually presently experienced but pulled from the memory unconsciously. Deja vu is the sensation that occurs when our conscious mind catches itself doing normally subconscious association. Some peoples minds experience this more often than others. These are the Shirely Mclains of the world. Swearing that we dreamt an experience before it happened is a common rationalization of that phenomenon. In fact our minds do not dream coherent narratives at all. Random firings in the brain(often in regions recently used, hence the incorporation of images and sensations recently encountered) are processed thru the amygdala or hypocampus (i forget) where in there are woven into a narrative of sorts in the act of recall.
For a test, write down the dream you had at the moment you awake. compare that with experiences the day before. There will generally be correspondeces. Then at the end of the day compare the events with the dream you had as you recalled it. Do this for a week. This type of scientific approach has been done and dreams were not found to have any relationship to the future, but much relationship with the past.
Selective perception, which means forgetting or ignoring the majority of sights and sounds etc. while taking note of a select few or one, is the reason we see coincidences like the toothbrush story. Our minds, always seeking patterns, takes special note of one when it occurs. Ask, was I looking for that style brush before I was asked to? Could I then just have not noted the style before? Does this experience happen often or seldomly as expected by normal statistical probability? How many similar occasions did not have a seemkingly providential outcome?
Knowing how our minds work and the way we perceive our world thru it prevents us from drawing hasty conclusions of a supernatural kind.