Hi there,
Given so little information, any solution might be the best, depending on the unknowns.
- if your search requirements are very light and simple, then a hand-made solution could be the solution. It saves you from adding a new piece in the stack (and the less components you have, the lower complexity issues you have, and the easiest it is to maintain)
- Solutions like ElasticSearch are really great because there's already so much in there. Really, it might be complex to scale (like so many solutions), it's not magic and requires you to learn it to get nice performances and results, but you can focus on getting nice results, rather than re-inventing the wheel if you need complex queries, distance function (tf-idf, custom scoring, ....)