Legal possibilities to get extension in my short term Schengen visas??

Ask the embassy - it's their job to answer questions like this, and only their answers are authoritative.
We have told you this before - why are you still posting basic visa questions here and not calling the embasy???

have you not read the Finnish migration website? They should have information on whether you can apply for long-stay visas from within the country or if you have to apply from outside the country. It's common to not allow applications from within the country based on my experience with immigration to other wealthy European countries:

http://www.migri.fi/frontpage

Also, what Beppi said. There is a lot of goodwill on these forums but I think it's wearing thin with these constant specific questions being posted alllll over the forum.

Hi owais.truefriend,

Your topic is now on the Finland forum.

Can you please avoid posting the same message on all the forums?

Thank you,
Christine
Expat.com team