In some cases a specific journal is one of the most important and relevant places for a research topic. So, is this normal and acceptable (for a pre-Ph.D. researcher) to have several papers published in that journal? I once heard from a professor that it may affect the CV in a destructive way.
If I have several papers published in the same journal, will people think that my papers were published not because they were good, but because I was somehow able to bypass the peer review process?
It would depend on the journal, of course. There should be no negative effect if it is a high quality, respected journal such as one associated with a professional society. A predatory journal would be a different matter of course. But the several papers in the same high quality journal have been reviewed by a fairly large number of independent reviewers.
Whether the editors would continue to accept papers from the same person is up to them, of course.
I don't think anyone would conclude that something fishy must be going on, just from the fact that you published multiple times in the same journal -- if it has peer-review.
However, since you mention the impact on the CV, where you decide to publish signals where your expertise lies. Among different journals with similar prestige, you may want to decide based on which audiences you want to address and where you see your specialty.
