Additional lives in Venice Mystery

Does anyone know how many points or puzzles solved it takes to gain an additional life in Venice Mystery? I got up to 4 lives, but don't know how. Now I'm down to 2 lives and trying to figure out how to add a life.
Thanks for any help.

As far as I can remember, you get an extra life every 250,000 points!
Try to remove stones with the same pattern in one rush and you get combos and better score.

This isn't fun anymore... I"m on level 46... and I"ve had to restart that level at least 20 times... I run out of stones that match and I have no helps.. like swap, shuffle etc... So whats a person suppose to do...If I can't match anything... I"m toast.. !

I just got fed up and quit the game.. but I was enjoying it till then.. I"ve read the rules.. but if I can't shuffle the stones and am stuck .. then what..??

Come on gamers .. give us a chance ok...? Oh ya.. don't be so darn chinzy on the hints... those pictures where we have to match to are nearly impossible.. and 3 lousy hints is rediculous... whats the point in make us frustrated...???? We won't buy your games and you don't make money.. How smart is that..?

I never did understand them taking a life away.. I really don't care.. I just want to be able to finish the level and go on to the next one...

Very frustrating guys... !!

@Caleryhart
Try to save some extras in the easier rounds to use them in the later stages. It helped me a lot to solve the game.

I am stuck on level 46 as well ...with no helps left and no stones will match. Is there a way to get one more help?