I find some white spots in my finger nails. is it harmful? how to cure it? thx

Generally no: White nail spots, or leukonychia, are generally harmless spots that arise most commonly from trauma to the nail matrix (where nail grows from). They are very common and the spots grow out with the nail and are eventually lost. That being said, some systemic conditions may cause nail discoloration, in particular liver or kidney disease. If u haven't seen a doctor in some time, maybe you should now.

Generally no: White nail spots, or leukonychia, are generally harmless spots that arise most commonly from trauma to the nail matrix (where nail grows from). They are very common and the spots grow out with the nail and are eventually lost. That being said, some systemic conditions may cause nail discoloration, in particular liver or kidney disease. If u haven't seen a doctor in some time, maybe you should now.