In the Time Entries tab, click on the Filters button and click Assignee. Click on the button for the Assignee filter to expand the list of available users, and choose one or multiple assignees.
If you do not have a Filter option in the search area, you may be restricted to viewing only your entries.
Note that depending on the settings of a user's project permissions, they may be able to see entries from all project members, entries from just a subset of members, or just their own entries. Project owners manage the project permissions for project members.