I think it is better to specify your field of study since international business contain a broad and important subjects. after that base on you field of research you should read the articles to understand the literature and base on theoretical foundation of literature you can find niche topic easily.
I would suggest that you study about - Internationalisation of services firms - i did research in this area - you can choose which type of service firms in services. consulting firms, auditing firms ... Services firms are playing and going to play an important role. if you would need more help - welcome to discuss
Digital opportunities for small and medium-sized family enterprises to gain competitive advantages in global markets
My Chinese PhD student is at the very beginning with this topic concerning Chinese family SMEs. In case you decide to work on this topic, we can be in touch
I suggest that you start with identifying what aspect of International Business you are interested in and then narrow down to a research area based on what you think is an unanswered question based on a preliminary reading of the literature. The research that you choose must resonate personally with you.