One really great thing about tactics trainer is the huge number of good tactics problems it has. With that, I find it very understandable that not every single one of these problems has an explanation in words that comes with it.

If you are looking for explanations, there are several good ways to go about that I know of and that I can recommend:

a) When you have tried a problem and failed it, you may wish to try once again, giving yourself more time and maybe try harder, before looking up the solution. (It is generally known that one most often learns most from those problems that one has tried at hardest and which one may have finally succeeded in solving by oneself.)

b) You can look up the solution. In many cases, this will already explain everything to you. In some cases, you might want to wish to think it over again, trying yourself to figure out why this is the solution.

c) If you want to look up an explanation, then have a look at the Analysis & Source file. For almost all of the problems, it contains computer analysis that will be able to answer many of your questions automatically. In many cases, this file will even contain explanations in words written by a tactics trainer moderator when he thought it might be helpful.

d) Have a look at the comments for this problem if there are some already. Your questions might have been discussed and answered there before you.

e) If all points mentioned above still leave you with open questions, feel free to write a comment to this tactics problem and tick the tracking box to get notified of answers. There is a very good chance that another user who comes across this problem later, or a tactics trainer moderator, will be able to help you with an explanation that solves your question. Sometimes this may take a little time, but often there will be an answer more quickly than you might have expected