"please try to understand" is short and natural, but your sentence is equally polite and soft, without causing offence.

I see you have not so good English language and you better use a simple sentence now "I want you to understand"

Thank you for answering my question.

Simple "Please understand ~" would also do, I suppose, because when you say something like 'please understand ~' it directly implies that you really want them to understand something and also when you say 'please understand' you don't need to tell them how would you feel about it however it will emphasis on the need of it. Oops. I did write it in comment :)