Ran an Interpol search with Silva as a surname.If that is a birthdate then it's 12 th February 1977? (Diogosilva12277), so that could narrow their search for who to look for. .
Silva is also quite common in Spanish speaking countries.
Didn't find a Diogo, but could be a variation of it.
Even with the DOB, it's finding a needle in the haystack though.
If I spoke Portughese, I'd had run the research.
A Portughese-speaking will accomplish much more than I can.