How to get divorce

The new marriage would be illegal

I do believe that bigamy is illegal in most Countries and that divorce is illegal in the Philippines.

Then what is the solution for this?  How to marry him again?  Because they are not happy their first marriage..

contact a lawyer, I am aware that there is a solution.

Annulment and do NOT get married again.

in Srilankan is legal to have more then one wife? you can do annulament in philippines , some people told me need one year and 200k php.

divorce you can in your own country ,in the philippines there's NO divorce possibol,but as i understand this will do to mary in an other country as the divorce will be legal in your own country

greets Dirk

I think it imay be nearly impossible for your friend to be legally married again in  Sri Lanka.
From the Sri Lanka government website here are the official lines:

'Completion of age of 18 yrs. by both parties as at their previous birth day.
The parties should not have any kind of relationship prohibited in law.
No party should have entered into any legal marriage which is valid at the time. '

The annulment in the Philippines is a long drawn out legal and expensive process.   The outcome. if it is successful, still does not entitle you to legally marry again.   

However, this is not the end of the world!

They will need an annulment. But it's not a quick process. It will be a few years before he is legally separated

You don't say if your friend wants to marry a Sri Lankan girl in Philippines or in Sri Lanka.

Separation makes no difference in Philippines, legal or not, the couple are still married until the marriage is annulled.

Marriage is for life in Philippines and the church and the government make it almost impossible for an ordinary person to get out of that contract. Ordinary people can't afford an annulment and even then many applications for annulment are dismissed.

This rules applies to Catholics only, if say you are Muslim then you are free from the law in Philippines, say I am Orthodox, this rule can not apply to me, and I know Philippines respect other religions, the rule is not the same for every one, Catholics can not get Annulment as  they are bound by religion.