Asslm Moulana
I have 2 questions.
Q. 1) Can a female go aboard to university and her milk brother to be a mahram? It will be for about 4 years.

Answer: If seeking such education would be necessary, then by all means she can travel with her milk bother.

If the knowledge sort is not necessary, then too she could travel with him, but such a situation would not be recommended. Travel in Islam must have a purpose intended for a specific positive outcome for self and humanity.  Traveling for mere play and not needed information and education would be disliked in Islam.

Q. 2) Can a girl marry her mothers milk brother?         Time: Saturday June 13, 2009

Answer: No.

Allah Certainly Knows Best.