Active Directory Issue!!!

It appears that you imply the DHCP Server in the AD. In order to restrict access permision to any given object proceed as follows:
1) Right mouse click and inspect the object property sheet.
2) Select the Security property tab.
3) Add the accessor object (Account Managers) if not present in the accessor list otherwise known as the access control list (ACL)
4) Modify the listed permission for the accessor object when selected to reflect only the permission whose meaning you understand and intend to allow; in this case you only want the Account Managers to see(read/browse) the DHCP Server object this means you will only allow READ permission for the Account Managers on DHCP Security tab.
5) Apply and OK the changes.
6) Test your modification by connecting as a user with only privileges derived from the Account Managers group to make sure there are no surprises.

Hope it helps.

Your group "Account Managers" should be "Security Group - Global".
Place "Account Managers" global group to be member of "DHCP Users" domain local group.
DHCP Users domain local group is for members who have view-only access to the DHCP service.