Hi There
I guess the first question to ask is what were you doing for volunteer work?
It is a bonus that you have lived/volunteered in Vanuatu for 5 months, but can be difficult finding work.
It all really depends on the line of work you have been in, your skills and experience, what qualifications you have, and whether there is a position that matches this in Port Vila, Santo or the outer Islands. Usually the outer island positions are mainly through NGO's etc.
If you volunteered through Aid work / Humanitarian work, you can definitely try contacting the volunteer organisations in Vanuatu as they want people with experience and qualifications.
Another idea is to keep a look out on the Vanuatu job forum, 'Wokikik.' (type it in google). This has daily job posts.
I am in my early 20's, female, and lived in Vila. I had all the relevant experience needed in the certain industry.
The main thing is asking yourself one question > If a local can do it, it means theres no point in hiring an expat.
Good luck and hope this helped