The search tools on MSE offer a large range of options which can serve to filter search results. Per the comments above, you can use the search flag
isaccepted:yes, but this is going to narrow your results only to those questions which have accepted answers. There are two major pitfalls with this approach:
When an asker accepts an answer, they are indicating that the answer is the one which helped them the most (or, really, they are indicated that they "like" that answer the most). This does not mean that the answer is correct, or that there are not "more correct" answers—it only indicates that the original asker liked the answer better than the others, for whatever reason (with one of the possible reasons being "no other answers had been provided at the time the answer was accepted"). By focusing on accepted answers, you are limiting the scope of your search to those questions which have answers fancied by the original asker.
Many askers never accept an answer. There are innumerable excellent answers on this site which have never been accepted (again, for who knows what reason). If you focus on questions with accepted answers, you are going to miss out on these answers.
Instead, I would suggest that you focus on questions with answers. For example, add
answers:m..n (where $m$ and $n$ are either integers or blank) to a query in order to find posts with between $m$ and $n$ answers (inclusive, e.g.
answers:2.. returns questions with $2$ or more answers). Or you can add
score:5 to locate posts with a net score of $5$ or more (highly upvoted questions are more likely to have good answers). The search flag
is:answer can also help you to focus on answers.