Common Query Access Issues

a) User cannot see a table they wish to query from in query manage
User does not have access to the table via one of their Access Group. Double-Click that they have the Proper Access group on one of their Permission lists an ad the table to an Access group if necessary.

b) A user cannot see a public query from search screen in either query manager or query viewer.

Once you have determined that the query does in fact exist, and I s indeed a public query, then the user probably does not have access to all the tables being used in the query. If a user does not have access to all the tables involved in a query, the search screen itself will filter out the query, so that it does not even appear in the list. Double-Check that they have the proper Access group on one of their permission lists and add the table to an Access group if necessary.