I have already applied a Schengen Visa as Visiting Family and Friends Visa. I was given 90 days from 28 of November, 2014 to 25 of February, 2015. I've flew from Philippines and arrived in Germany 30th of November, 2014 and went back to my country (Philippines) last 23 of February, 2015. I am now re-applying for a new visa. How long should I stay in Philippines before I can go back to Germany again for the same visa I have applied before.
There is no required number of days before reapplying for a new visa, you can reapply as soon as the first one expires. There is no mention of that in any official website of any EU country.
Of course the officials might think twice before approving the new visa due to the short period between the two, but that shouldn't be a problem if you have all the requirements and most importantly have strong ties to your home country (a job, good pay, etc.).
Remember one thing, the 90/180 rules still applies regardless it is on a new visa or not.