Date modified is wrong when searching files

I'm experiencing an issue where the modification date of some files, (mainly image files I think), is incorrect when using "Searching All My Files" in the Finder.

The file i'll use to illustrate the point is a .jpg image that has been modified and saved as a .psd from Photoshop. (Samson Gold.psd in the screengrab) It isn't just this one I have the problem with, there are multiple instances.

The original .jpg file created was on 19 Oct 2016 and I've opened it in Photoshop, made some changes, added layers etc. and saved it as a .psd yesterday, 26 Oct 2016.

I utilise custom criteria to search "All My Files" so it includes all items created by the Adobe CC apps (for some reason it doesn't show these by default) to create a record of files i've worked on over the past few days.

However, the modification date is correct when I "Get Info" on the file. You can see in the screengrabs that it seems to retain the creation date rather than showing that it has been modified - even though now it is a .psd, not the original .jpg.

I've included a couple of screengrabs to help.

Hope someone can help - its driving me mad! 🙂

cheers
Lee