This is a straightforward question about grammar, asking if "adjectival clause" can be used in the same way as "adjective clause."
I didn’t vote on this question, but those who did nominated lack of research as the reason to put the question on hold or to close the question. The reason is provided in the banner at the top of each closed question.
On Stack Exchange, there is an expectation that people who ask questions show what they’ve found. This is partly a courtesy to answerers so that people don’t waste time detailing what the asker already knew.
Another part has to do with the history of the site, which started as a Q&A for programmers. They wanted to avoid the gimme the codez mindset. In today’s context, it can be described as a do my homework for me approach, which isn’t what Stack Exchange is about.
Stack Exchange was set up to be a repository of good questions on a specific topic, together with expert answers to those questions. Requiring ‘research’ helps to keep questions interesting and at a high quality, which in turn helps retain experts within the community. It also helps to pinpoint the specific issue so that future visitors can drill down to answers addressing that specific issue.
Since the answerers are almost all volunteers, there is no financial obligation for them / us to stay (to help provide good answers). Each topic or community will typically have a pool of common questions, and scrolling through essentially the same question over and over again isn’t particularly interesting or captivating.
But if someone has tried to find an answer to their own question, the contradictions or puzzles that emerge are often interesting and worth thinking about.