Google Scholar has no submission form for journals, which surprises most editors. Inclusion follows from meeting its technical requirements and being crawled. When a journal is absent, the cause is almost always one of four technical faults rather than anything about its editorial quality.
The metadata is not in the tags Scholar reads
Scholar reads specific meta tags on an article page: title, authors, publication name, date, and the address of the full text. A site that displays all of that beautifully to a human and emits none of it in the markup is invisible, and the fault is not visible from any page a person looks at.
This is the most common cause by a distance, and it is a configuration fix rather than a project.
The full text cannot be reached
A crawler cannot sign in, cannot accept a cookie banner and cannot follow a JavaScript link that only appears after a click. If the PDF sits behind any of those, Scholar sees an abstract page with no article attached.
The addresses keep changing
Every site redesign that changes article URLs without redirects breaks every existing citation and forces re-indexing from scratch. Stable addresses matter more in scholarly publishing than almost anywhere else, because a citation is supposed to still resolve in twenty years.
There is not enough of it yet
Scholar is not obliged to index anything and gives no guarantees. A journal with two issues and few external links may simply not have been picked up yet, and there is no queue to join. The correct response is to fix the first three and publish consistently.
What to check first
Open one article, view the page source, and search it for "citation_title". If it is not there, you have found the problem, and it is the cheapest of the four to fix.
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