I have refused your application for a visit visa because I am not satisfied that you meet the requirements of paragraph(s) V4.2 because:
You have applied for entry clearance to the UK for 18 days. The information you have provided on your application form and the supporting documents you submit allows me to assess whether your circumstances and intentions are, on the balance of probabilities, as stated.
On your Visa Application Form (VAF) you have stated that you intend to visit your sister for 18 days. From 2013 until June 2016 you studied in the UK. You then returned to the UK as a visitor in March 2017 after being issued a 6 months visitor visa on 21 February 2017. On your previous application you stated that you intended to stay in the UK for 14 days to look for a university. Notwithstanding this you have stated on your VAF that you only returned to Russia on 19 August 2017. You therefore remained in the UK for 5.5 months. It is not clear what you did in the UK but I am not satisfied that such a prolonged stay is commensurate with the actions of a genuine visitor. This causes me to doubt your current intentions.
You are unemployed and financially dependent on your mother. From the documents you submitted she appears to have an income from a pension. This amounts to 5848 RUR (£75) (£1 = 78 RUR) a month. It is not clear from the evidence submitted where the savings are from and I am not satisfied that the funds in the account are genuinely available to you.
Taking all the evidence into consideration I am not satisfied that your current circumstances are such that you are genuinely seeking entry for a purpose that is permitted by the visitor routes (Appendix 4.2 (c)). Nor have you have shown that your circumstances are such that you will leave the UK at the end of your visit (Appendix V 4.2 (a)).
For the reasons above I am not satisfied that you have sufficient funds to cover all reasonable costs in relation to your visit including the cost of your journey, any costs relating to dependants and the cost of any planned activities. Your application for a visit visa has been refused under Appendix V4.2(e).
I have therefore refused your application because I am not satisfied, on the balance of probabilities, that you meet all of the requirements of the relevant Appendix of the United Kingdom Immigration Rules. Any future UK visa applications you make will be considered on their individual merits, however you are likely to be refused unless the circumstances of your application change. In relation to this decision there is no right of appeal or right to administrative review.