There are some headings which lack preciseness such as: Exercise 1.17 from Introduction to Lie ALgebra and Representation Theory by Erdmann and Wilson and Just and Weese II exercise 13.20. When one is interested in question and does not have the mentioned book, has to face trouble. So should we use book and exe. no. in heading?
So should we use book and exe. no. in heading?
Depends on what the alternative is. The title "Exercise x.y in Book Z" is better than "Help with exercise". I'm afraid that if we start telling users "don't put exercise number and book in the title", the result will be more of "Help with PDE problem" and "Probability question".
Of course, a descriptive title is best, but it's the reality that many question askers do not know the subject matter well enough to come up with a good title. Someone, perhaps a person answering the question, may have to edit the title to make it more descriptive.
When one is interested in question and does not have the mentioned book, has to face trouble.
Note that in both cases the problem statement is contained in the body of the question (as it always should be).
General recommendations on composing a title are found in A good title. This is a CW post originally written by Lord_Farin, to which further insights can be added by the community.