To follow up step by step by patient inquiry or observation; to trace or track mentally; to search into; to inquire and examine into with care and accuracy; to find out by careful inquisition; as, to investigate the causes of natural phenomena.

investigate scientifically; "Let's investigate the syntax of Chinese"

conduct an inquiry or investigation of; "The district attorney's office investigated reports of possible irregularities"; "inquire into the disappearance of the rich old lady"

Conducting a search or examination of evidence so as to understand a concept; inquire into systematically