No, it's not true. Fortune tellers use a technique that is essentially made up of generalizations that every single human being goes through in their life.
For example: I predict you will have financial success in your future.
The reality from this: say you become a teacher (not a very high-paying job). You would think that you are not successful, correct? But then say five years down the line you hit a big jackpot at the casino for $5,000. The fortune teller can simply claim that is what they "foresaw".
Another example: I predict you have a wonderful romance in your future.
The reality: of course you will. Or, at least, you are likely to have one. Everyone falls in love at some point or another (I know, not everyone, but it's few and far between. This is based on generalizations, after all). Plus, there is the subconscious thing working here. Say a fortune teller says this to you, then two days later you're at a bar and your eyes lock with those of someone else. Your heart flutters, your head spins, and somewhere in your subconscious you're thinking "the fortune teller might be right!" which then affects your actions from then on, and may lead to a self-fulfilling prophecy.