Some collection of students' theses or dissertations I want to looking for information in graduating level. Is there any collection or library which provide students' theses or dissertations of many universities? Googling just find library for each university.
For British doctoral theses, check out the British Library archive. Many full texts are available.

As Ri49 says, you can see TEL for theses from France...they claim 42000 full texts so far....