You did not share the searches but I suspect that you are doing this:
sourcetype=MyEvents ...
If so, the solution is to specify the index in your search like this:
index=MyIndex sourcetype=MyEvents ...
Your admin user has more roles that the other users and one of these has a the important index in the Indexes searched by default" setting. so his searches had results without having to specify an index. The other users, even though they have admin role, lack this other crucial role. This problem is the result of a very common but VERY bad habit. A user-level best-practice is to always be as specific about your search query as possible and, to that end, always include index= and sourcetype= directives. What is worse than a no-results situation is a wrong-results one where you get one set of results but your boss gets a different set (because you are not in the same role and do not have the same Indexes searched by default setting). There are 2 ways to preclude this problem. You can change this setting to All non-internal indexes in the user role so that every new index is automatically included in non-index-specific searches without any extra administration. The better way is to set it to nothing (empty) for every role thus forcing users to be habitually index-specific!
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