Following up on ssandv's "state your problem more clearly" -- more "precisely" would also be a "good thing"^{Reg SM}. Re code tags, see Markup in the Monastery. And does "it doesn't work" mean you're having trouble writing a regex that matches what you want or something else? (If so, what?)

Then you may want to explain whether "I want the BLABLA's with the integer '2'" means

• those single instances preceded by a 2
  or
• those single instances followed by a 2
  or
• those multiple instances after a 2
  or
• etc...?