How to use the users query syntax to retrieve a list of users?

I have in my application a requirement to check users based on his user_id field. To solve this, I’m using the Java SDK. I need to execute a request to list users based in this input data:

String[] accountIds = {"a", "c"};

For this I create a filter with a query like this

user_id:a AND user_id:c

In my Java code:

UserFilter userFilter = new UserFilter();
userFilter.withQuery(filterBuilder.createFilter(accountsId));
Request<UsersPage> userListRequest = managementApi().users().list(userFilter);

But when I retrieve the list on items, I expect to have two, it returns 0. If I test the same query but with only one item in the accountIds field, it works as expected, the detail of the user is shown.

How can I retrieve a list of users based in these criteria?

Thanks

I used this to solve my problem:

user_id:(a c)

Found the solution here: Can Users be queried in bulk? E.g. Find users in this list of emails? - #2 by MerrickClark