research
n. uncountablen. the careful study of a subject to find out new facts or information. You do this when you need to learn more about a topic for school or work.
n. systematic investigation into and study of materials and sources in order to establish facts and reach new conclusions. Often used to describe academic or scientific inquiry.
She is doing research for her history project.
The university received a large grant to conduct medical research into rare tropical diseases.
Extensive market research suggests that consumer behavior is shifting toward sustainable products, prompting many companies to redesign their packaging and supply chains.
Early Modern French rechercher (“to examine closely”), from Old French recerchier (“to seek, to look for”), by surface analysis, re- + search.
The noun is uncountable; use 'some research' or 'a piece of research' rather than 'a research'.
I did many researchesI did a lot of researchResearch is uncountable and does not have a plural form in general usage.