No one can help you in collection of evidence(s) of second marriage. You are to fight your war if you want to send your husband to jail u/s 494 IPC.
What is the opinion and advise of your lawyer who is well aware about facts and circumstances of the case, an able, competent and intelligent enough to advise and proceed.
If you are dissatisfied with the ability, competence, performace or behaviour of the lawyer engaged and paid by you s/he should be changed immediately.
It is advisable to consult another local prudent lawyer for better appreciation of facts/ documents, professional guidance and proceeding.
However, if you are located in Delhi and feel so, may contact me with relevant records (on appointment) at: Chamber NO 647, Lawyer's Chamber Block, Dwarka Courts Complex, Sector10, Dwarka, New Delhi-110075 Cell # + 91 98911 52939 email: firstname.lastname@example.org or visit: vakil-saab.com