The term 'look into closely' can be summarized by two crossword solutions: 'PROBE' (5 letters) and 'EXPLORE' (7 letters). Probing is the act of examining something in detail, often with the use of specialized tools or techniques. Exploring is the act of searching for information or knowledge, often through observation or experimentation. Both terms suggest a thorough investigation of a subject, and are often used in the context of research or problem-solving.