A keyword is a significant word in a title or document. Your keywords relate to the key concepts you identified in your concept map.
When creating your search statement you will also need to come up with synonyms (words with the same or similar meaning) that will also retrieve relevant information. Keep in mind that some words have multiple spellings. List all variations in your list of synonyms.
It is useful to use Boolean operators, truncation, wildcards and phrase searching in your strategy. These elements tell the database how to interpret your keywords and will give you more relevant results.