Dear Professor ×××
I am in ××× Institute of ×××, Chinese Academy of Sciences. I am writing to request your assistance. I search one of your papers:
。。。。。。。。。。。。。。。。。（你的文献题目）
but I can not read full-text content, would you mind sending your papers by E-mail? Thank you for your assistance.
Best wishes !(or best regards)