Relevant keywords are indispensible for a workable search, whether in books, articles or even the web. Think about your topic before you begin. If you phrase it in the form of a question, it might help you select the most useful keywords. For example: What are the problems of electronic home monitoring that can arise (possible keyword italicized). these are reasonable possibilities.
These might work the best in different combinations depending on the type of resource you are using: electronic home monitoring, home monitoring, home monitoring and problem* (the asterisk is a function called truncation which allows you to expand your search). All possible endings of the word will be brought up in addition the word problem: problems, problematic, etc.
You can limit it further, instead of using the word problems* you can try probation. you can be as specific as electroninc monitoring and sex offenders or electronic monitoring and recividis*. Above your results list in the Proquest Criminal Justice Database there are other subject terms you can click on directly. Using the main term along with parole is uneccessary since it would be implied. This kind of strategy holds for many different searches.
Although there are generally fewer books on any given topic than articles, for this topic you still might try one or more combinations of the 3 words to get what you need without the addition of parole. Look at the subject lines and Tables of Contents when you call up a book title to get more ideas.
If you are trying a topic such as sex offenders and recidivism, there are other options. For example, think of other terms for sex offenders and you may have a very different search.