When selecting key words for SEO pieces, it is essential to contemplate the keyword's applicability to your theme and its query volume. Start by researching related topics and terms that are popular in searches. Identify relevant long-tail keywords with low competition, as these can be easier to rank for than more competitive terms. Utilize tools such as Google Trends or Keyword Planner to help you determine which words have high search volumes but low competition levels. Additionally, make sure your chosen keywords appear naturally throughout the article so that they don't seem forced or out of place. Finally, always keep your target audience in mind when selecting keywords.