Do i have a chance to adopt a healthy child from abroad or will he have problems?

Usually healthy: If the child has any health problems they should be disclosed to you in advance. Obviously there is a chance that something wrong may be missed or overlooked. Common (but not serious) problems with international adopted children include being small or underweight, parasites, tuberculosis(will be tested for), developmental delays, emotional problems and learning problems. Problems may show up later.

Choose wisely: It depends a lot on what country and what circumstances the child lived in. South korea, e.g., has totally separate systems for children to be adopted internationally from those adopted within the country; you can guess where kids with poorer prospects go. Also, former soviet countries had notoriously poor orphanages with many damaged children. Agencies exist to help prospective parents screen.