Should I wait for the next Ph.D. openings? I'm finishing my master's degree in theoretical physics (probably with distinction) and have published a paper. 

I'm searching for a Ph.D. position in theoretical physic in Europe, but I can't find any position which I'm passionate about. I think, there will be more opening in 6 month. On the other hand, I will be then 30!

Would you suggest me to wait for a position which I really love? Or should I apply to for a position which is interesting but not that much? The problem is that I'm not sure about future!
I'm not sure where in Europe you are looking, but in my experience not all positions are advertised. I would suggest to use your network (especially your MSc advisor) to contact the labs you are interested in and inquire about opportunities.

In both European countries I am familiar with (Germany and France) there are government PhD funds that are allocated on individual application from the student. So often, you can get professors who are willing to work with you if you apply for your own funding, even if they don't currently have funding for an open position and therefore aren't advertising anything. There are usually yearly or twice-yearly deadlines for this.

Whether openings are continuously advertised or clustered around certain dates will depend on your country's habits. What makes you think that better positions will open in 6 months? Are there some big grants being awarded at that point?