I forgot about using quotes when there is more than one word when searching, hopefully that's all I needed. I'll try again this evening.
Just an update, so adding the quotes helped somewhat, "steve vai" worked but "lacuna coil" still did not.
I also noticed that in the scenarios where I have 3 versions of the same ablum, 16/44.1 flac, 24/94 flac and mp3 I was only seeing 2 albums in Artist View and also in the default view when going through the Artist or Artist Album folders. I was seeing my CD album and then an undisclosed 2nd one

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As I looked at the 2nd one I could see that there were 2 of each song, I assume one was the 24/96 and the other was the mp3. The song numbering was weird as well, it went 001, 002, 003, etc. plus the song name. I looked at the tag info and noticed that my CD album had (CD) at the end of the album name field but both the mp3 and 24/96 albums were tagged the same and simply had the album name. I then went and put (mp3) at the end of the album name tag field for the mp3 album and could see that the database was updating so now in theory each album is unique via the album name tag. When I went back to look I still could only see 2 versions of the album, the CD album as before plus the 2nd. The doubling of the songs was gone but there was no 3rd album showing anywhere in the list. I also noticed that the songs were all still numbered 001, 002 , 003 plus the respective song name rather than simply 1, 2, 3 etc. or no number at all. I would have thought that would have corrected itself but it looks like the database is still confused.
I re-enabled update database and it did, very quickly so I'm wondering is there a way to force it to completely rebuild from scratch, maybe that might fix the oddities I'm seeing.