I see this phrase being used often by non-native speakers, and it never fails to strike me as incorrect:
"In this research, [...]"
I also note that Wiktionary and Merriam-Webster consider that usage correct, but "rare" and "formal + old-fashioned". This Quora question has a comment that says that it is restricted to British English, too, but there are no sources for this. Searching for occurrences of this usage on Google is hard, because "researches" could also be the verb, and "a research" is usually followed by "paper" or "group".
So, is research as a countable noun really used by native speakers, or has it already fallen out of usage and is only kept alive by awkward translations?