Hello @Taz I’d echo @roberday in his comments that exposure to lots of things can be a strength in itself.
In terms of books, it is very much what you want to learn. If it is testing in agile methodologies you can’t go far wrong with Agile Testing and More Agile Testing by Lisa Crispin and Janet Gregory. The book Explore it! is a very good introduction to exploratory testing or there’s lots of information on http://www.satisfice.com/ James Bach’s work on Session Based Testing and Rapid Software Testing with Micheal Bolton are both well worth looking at.
If you want to look at automation, which many do these days, then https://automationintesting.com/ is a worthy starting point but there are a lot of resources out there and many are highlighted around the club.
Of course tailoring your CV towards your strengths and keeping it up to date is useful too and there’s a good discussion here, CV’s: How Do You Write Yours? I uploaded my CV in that thread and there’s a lot of other tips too.
Good luck Taz.