trouble with finding files

I don't seem to be able to get the web page access to my nexus to search properly. For example, I definitely have one picture, which is named IMG_[numbers].jpg

Does this app allow partial name searches? Using IMG, IMG*, or *jpg is not coming up with any results. If I click down into the photo directories it does see them. Is this not supporting wild card searches?

On a related note, I cannot find *any* kindle books. I downloaded the Kindle app, and used that to download my entire library. Everything shows up fine from within the app. But I cannot seem to find any books ON the nexus 7... if I use airdroid and go into the folder named kindle, it has one folder named acw, which appears empty. I've tried a few searches but came up empty (and then had the above difficulty when I tried proving airdroid's search worked when given known files).

Any help greatly appreciated, whether it's on the airdroid file search, or on the incredibly frustrating kindle app (I can *never* seem to find the physical kindle book files _ever_ no matter if it's an iphone, a kindle, or now an android tablet, that I've downloaded my kindle books to. I really hate not being able to see the actual *.azw files anywhere... >.<

This is very strange. It is quite impossible to search files. Only when you are in the right folder and use the right and complete name, you can find the file....But... When you know exactly where the file is and you know exactly what the name of the file is, you can find it by yourself. No need for a file search program.
I hope that a true file search, with wild cards and through all folders will soon be implemented in this otherwise fantastic program.

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