While @JDM-GBG is correct that only nouns can be used with " 's ", I would also like to point out that it is not always used when a noun modifies another noun.
For example when talking about "Kososvo's declaration of independence", you are referring to whatever Kosovo did to declare independence. However, typically with proper nouns, referring to a specific document, event, building, etc. an " 's ", is not needed. See:
These proper (or close to proper) nouns are also usually preceded by the article "the. " Both of these attributes imply that there is only one of whatever you are talking about.
In regards to your International law view vs. International law's view, similar rules apply but are not as strict because they are not referring to one thing.
saying "looking from the international law view ..." makes it sound like you are referring to a generally agreed upon perspective or set of guidelines to evaluate with that relate to international law.
but saying "looking from international law's view ... " sounds like you are looking at the actual international laws and then interpreting them (which may or may not be agreed upon). However, this phrasing sounds weird to me and I would more naturally say "the view of international law".