Having "good search volume" is in reference to the amount of times per month your keyword is being searched. It's ideal to target keywords with higher search volumes as this gives you an idea as to what kind of traffic you can expect to receive in the event that you're actually able to achieve ranking for that particular keyword.
Now, this is only half of the equation...
Secondly, you'll want to do a competitive analysis on competitor sites for that particular keyword where you'll want to review the page that's indexed to see how optimized it is for that keyword. Some other things you'll want to review is the PA/DA (page authority/domain authority) of that ranking site so you can have an idea as to how difficult it'll be to outrank them for that keyword.
Understanding the playing field for any given keyword will also give you a good idea as to what kind of links you'll need to have built to your site to have a fighting change of getting ranked in a position that will actually be profitable.
I can go more in-depth with this but I'd be having to write a few pages... Haha
Best of luck!
