How can i get oAuth Token from PHP SDK.

How can i get oAuth Token from PHP SDK.

HI, there.
 
i have a question.
usually, i use PHP SDK to access ZOHO CRM.
today i want to get records with criteria with the word 'before or 'afler' and so on. 
so  i need to use a COQL Query by myself.
May i use the access Token  from SDK ? how can i get the Token?
thank you.