2 combobox values if then else vba

I need a vba script that will choose one list from 1st combobox and then another list from 2nd combobox then generate a report.

Sample scenario 1st combobox if choose sales 2nd box if choose may then sales report will generate for month of may.

1st combobox if choose expenses 2nd box if choose (month) may then expenses will generate for the month of may.

Please help ... I only have combobox list ready my script.