How to find a journal for publishing my method without applying it to specific real data? I have developed different algorithms as PhD studies. My algorithms work fine and have some limitation as with any algorithm. My work basically is developing models that help other people in their area. While, my work is very useful for many areas, especially finance and health, I had no specific real data (e.g., finance, health, etc.) to work with. Therefore I worked with general real data sets. For each model, I used several data sets. 

My study was on my behalf (so there is no third-party funded project). My supervisors were very happy with my works.
Now, after I have been awarded my PhD. degree (as a monograph), I am really upset to not have published my works.

I tried to publish but all journals I submitted to rejected my papers as I do not use challenging data that they are interested in.
How can I find a suitable journal to publish my work? 
Are there journals that are not interested in a specific area of real data?
I know that Elsevier publishes MethodsX or journals that focus solely on “Materials and Methods.” Perhaps those may be a better fit.

I don’t see why a typical journal wouldn’t consider that just because of the data set. If thats the case, I would put more emphasis on the model’s strengths and implications in the field.