Law / Information on which documents are needed to obtain a visa for a visit to Poland (non EU citizen ) [18]

Merged: Wife is studying in Poland. Family visit visa process for non-EU citizen

my wife is in Poland for study of master in sociology. I want to meet her in Poland what is the process to get visit visa? She did not work in Poland i am supporting her for study. Please help me how to write the purpose of visit? I want to meet her, her university and teachers as well. and what is the chance to get family visit visa???