How to fix "Non-existing setting" error from robotframework and seleniumlibrary?

I am trying to run a script to search for the keyword "mdh" and to show mdh.se as a result. I installed robot framework and selenium library and this is my script which I wrote in sublime text and saved as a .robot file.

*** Settings ***
Library Selenium2Library
Suite Setup Go to homepage
Suite Teardown Close All Browsers

*** Variables ***
${HOMEPAGE} http://www.google.com
${BROWSER} chrome

*** Test Cases ***
Google mdh and find mdh
Google and check results mdh www.mdh.se

*** Keywords ***
Google and check results
[Arguments] ${searchkey} ${result}
Input Text class_name=gLFyf gsfi ${searchkey}
Click Button class_name=Tg7LZd
Wait Until Page Contains ${result}
Go to homepage
Open Browser ${HOMEPAGE} ${BROWSER}

When I try to run the script with robot mdh.robot it says there are 5 errors.

C:\Users\malvi\Desktop>robot mdh.robot

[ ERROR ] Error in file 'C:\Users\malvi\Desktop\mdh.robot': Non-existing setting 'Library 
Selenium2Library'.

[ ERROR ] Error in file 'C:\Users\malvi\Desktop\mdh.robot': Non-existing setting 'Suite Setup Go to 
homepage'.

[ ERROR ] Error in file 'C:\Users\malvi\Desktop\mdh.robot': Non-existing setting 'Suite Teardown 
Close All Browsers'.

[ ERROR ] Error in file 'C:\Users\malvi\Desktop\mdh.robot': Setting variable '${HOMEPAGE} 
http://www.google.com' failed: Invalid variable name '${HOMEPAGE} http://www.google.com'.

[ ERROR ] Error in file 'C:\Users\malvi\Desktop\mdh.robot': Setting variable '${BROWSER} chrome' 
failed: Invalid variable name '${BROWSER} chrome'.

Am I doing something wrong?