Don't know if there's a formal name for it, but a graduate student explained it to me, back when I was in college... it's the particular confirmation bias in which experiment/study observation methods have greater acuity in detecting the factors that prove a theory than those which disprove a theory
Yeah, studies that confirm something, especially those that overestimate the effect as larger, get published more because they are making a claim for something hehe. I made a post a few months ago on a similar issue, that more negative research is needed to validate the positive claims in studies.