@ the developers
To be sure it isn't my server I did a fresh install on a different one free hosted by altervista.org.
I just created two albums and performed a search on the tags auto generated by the upload.
Same result as above, nothing is reported by the search, even adding new tags.
So I installed on both the free server and mine the nightly build of the 26 of july. Everything works fine now, search function and of course dynamic albums.
PS: I'm putting a "solved" tag on this topic.