permission to see other users activities connected to my client

Hello,may be somebody will show me the direction, I need to add permission for users to see content of activities attached to their accounts by other users. General rule is that no activities of other users can be seen in group but those which are attached to my account - that is the goal. Owner access profile add permission to almost all objects with edit/create abilities and default access profile gives ability to see records (view only). Checkbox view all records is unchecked, so I have to use other option to add proper settings.
regards