Hi! I wish everyone strong health.

My name is Vadim. I am living in Kazahstan. I am working as a doctor in a small clinic, and I would like to widen my lexical fund of knowledge of English, which helps me to know more about modern medical innovations.

[Good start.  I used 'widen' because that means you want to expand your  own knowledge.  'Spread' is used if you wanted to spread your knowledge to someone else.]