* "I know how you feel"
You'll never know how one feels being unemployed. It's miserable at times. Sympathising is tolerable, but it may not be acceptable always. There could be a point where he/she may snap back saying, 'I bet, you don't know how I feel, so stop saying that!'. When you get rejected out of more jobs, the lesser you would want to apply for the other jobs. It is a normal feeling of rejection. Talk about something else instead.
* "Why don't you study further?"
By asking this question, you are indirectly indicating that he/she is wasting time at the moment. Giving suggestions must be minimal. You must try hard to not let them feel worthless by any means. Though they have the right degree for the job, they may not be getting a suitable job opportunity. Or may be they wouldn't want to study any further at all. You may not want to coax them any further on this one.
* "How's the job search happening? Have you tried this job site?"
In general, ask them "hey, how are you doing?". Try not to flounder for things to talk about, lest you get a vague response. Just avoid talking about employment. That is it. Make sure you wouldn't want to put them down. Talk about another subject where the person can listen and grow instead. Make the conversation more interactive.
* "I have to work, you know?!"
It is real harsh when you say, "I can't really talk to you now, coz I have to work you know?!". Call them over for a drink or to hang out, when you're done with your work instead. Try not to make them feel that they are extremely jobless and are a real pain to you. It should not mean like they can't afford to be your friend because they're unemployed.
* "When would you taste the real world like me?"
The question might de-motivate them out-rightly. There's a time for every human being to experience different phases of life. It may be your time in the corporate world now, but it could be their time to be employed tomorrow. So, take it easy on your words. Give them positive assurance of getting a job soon.
* 'That's OK, you don't have to spend!"
Unemployment normally leads to more savings and lesser expenses. It defines all aspects of their existence. Throw some light on sharing, because you care for them. Do not be guilty and loose your relationship with the person, by mentioning that you'll have to spend it all on him/her each time, due to his/her unemployed status. They may not express their lack and they may not meet up with you often, but that's alright. Understand and adjust.