i need a recruiter do recuit work for me , it is a long time cooperation

Our company need a lot partime medical academic writers and medical proofreader work with us for a long time , but we are not familiar with this kind of platforms like freelancer and Upwork .So we need a recruiter help us to do the recruit work for a long time . here are some requirment for the recuiter : 1 we need this one have a lot of free time and reply me fast. i am not good at english ,so this recruiter should have a good patience . 2 he or she must have enough experience to do recuit work on freelancer or upwork before. 3 If he or she is major in medical is better ! because what we need is most medical academic writer and proofreader . 4 I am from china ,if some one have a similar time with me ,will be better !