Qualified means something depends on another action occurring. If your friend receives a qualified offer on her house, that means something else has to happen — like a bank approving the loan — before it's sold.
Qualified is an adjective with multiple meanings. Employers seek the most qualified applicants, meaning those who have the most experience and relevant training. Being qualified might also mean you have paperwork that shows you had certain training or meet certain standards. Or qualified can mean "partial" or "incomplete." If you approve of something but others need to agree before it's final, you would give your qualified approval.