MongoDB arrays can sometimes feel slightly more complex to query than expected, but with a good understanding of the nuances of Mongo Query Language, you can effectively retrieve data from these collections. The primary method for querying documents in MongoDB is the find() method, which allows you to specify criteria for matching documents based on their field values, including array fields. You can use dot notation, $elemMatch and $all operators, as well as advanced techniques like unwinding and limiting array elements within the aggregation framework to query arrays effectively. To improve performance of array queries, indexing, query optimization using explain() method, choosing efficient operators, limiting data, avoiding unnecessary array scans, unwinding and limiting array elements, and combining these methods can help ensure optimal execution time and efficiency for your MongoDB application.