I'm using topical Finasteride 0.1+%Minoxidil 5 % for 2 years and still, my hair density is less at the crown -- any suggestions?

Hair loss needs an in-person evaluation. I recommend getting a formal evaluation with a hair loss expert to go over your condition and advise you on best treatment options. There are great non-invasive options like prp/progesterone and/or hair transplantation. See an expert. Best, Dr. Emer

The best overall option would be to have a hair transplant surgery. If you are looking for a non-surgical solution, I would recommend oral finasteride instead of topical. You can continue with minoxidil topically or add Z82 which contains ingredients that enhance penetration and promote growth. Finally you can add laser therapy to your non-surgical regimen.  

Good work on doing something to stop your hair loss.  Doing nothing absolutely does not work.
The issue though is the treatment you are using is not as effective as it needs to be.  Minoxidil is about 40% effective, and finasteride is 60% effective, which gives you an average of 50% effective.  that's not even really a pass mark.  I would recommend you looks for something more effective such as Stop and reGrow which is rated at 95% effective.
Best of luck!

You will want to have a chat with your physician about all the options. They include oral finasteride, topical minoxidil with microneedling, low level laser, PRP, ketoconazole and zinc pyrithione shampoos, essential oils (Rosemary), saw palmetto, oral pumpkin seednoil and even low dose (0.25-1 mg) oral minoxidil. Hair transplantation and scalp micropigmentation could be options to at least consider. Speak to your physician about what the best steps are for you.

If you are not getting the effect you want, see a doctor who might direct you to a better approach than what you are now doing