Well, I've been using eSword for decades, and there's a great feature I've only just discovered. It's an option that I've seen in the menus but never tried it because I thought it was just the same menu option of a button already among the other buttons I push from time to time... This is one of the most significant features of eSword and possibly the most underestimated feature of eSword...
The feature? "Extended Search" under the "Dictionary" and "Commentary" menus.
The "Extended Search" feature allows you to search every dictionary module or commentary module in your libraries. it could find a Strong's reference, name, keyword, etc, etc. Sadly, it doesn't work with Hebrew, Aramaic, and Greek expressions.