How to install Install-Module in Powershell 4

Question

I have Powershell 4 in a Windows Server 2012R2:

Name                           Value
----                           -----
PSVersion                      4.0
WSManStackVersion              3.0
SerializationVersion           1.1.0.1
CLRVersion                     4.0.30319.42000
BuildVersion                   6.3.9600.21616
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0}
PSRemotingProtocolVersion      2.2

But I cannot use Install-Module or Find-Module or Get-InstalledMoule....

Install-Module : The term 'Install-Module' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try
again.

Neither Set-PSRepository.

How can I install this feature for installing other modules that I need?