Almond trees are actually one of the easiest trees to grow and are so easy that where I live - they spring up everywhere like weeds - very rapidly and always where you don't want them to be
You don't say what type of climate the almond trees were being raised in - but am assuming that it was suited to growing peaches and almonds - in which case the following may be of help.
Almond trees belong to the same family as peach trees and although they require the same climate and plenty of sun they don't require too much in the way of TLC - as they prefer less water and virtually no fertilizer.
Although these trees will start to bear nuts from the early age of 3 - 4 years old - as they are not self pollinating - they need to be planted with at least a couple of other varieties in order for them to produce a good crop.
The only other reason I can think of as to why your almonds didn't produce - is that sometimes if the blossoms get caught by frost - that too will prevent the trees from producing a good supply of nuts.