First open the profile of the user whom u want to send friend request.
after that,click on 'add friend''.
then the friend request will be sent.
open the friend list and in the corner there is a option ''enter friend's nickname''.
enter the name of the user and and press enter.
after that,list many users with that name(or starting with that name) will come.
the user whom u want to send request take your mouse pointer on that user's profile and click ''add friend''.