What were you doing in Russia and Cambodia?

When I passed customs and immigration in Los Angeles and showed my passport, I was stopped and profiled. "What were you doing in Russia? What were you doing in Cambodia?" the young man in a uniform asked me. I did my best to explain. He sent me to the inspector. Finally I told him, "It's a low-budget film," and he seemed to believe me. Here I am trying to give a more cogent explanation. Let me know if it makes any sense. Thanks to all who helped me. The blog is approaching 5,000 page-views, so I know someone out there is reading. Good luck to all. I plan to wrap it up soon.