調べる：しらべる：$$$ : to look up in a dictionary, to check tomorrow's weather report. To find out about the blood type of your favorite singer.
検査 けんさ: investigation, inspection, review: (fiancial audit, smog check, check the condition of goods that roll off the assemby line, etc). Has the nuance of a test where something passes or fails.
調査・ちょうさ： an investigation. (emphasises that there are no correct answers, and implies that the investigators are talking to someone, asking questions directly): (usually used about polls, surveys, and detectives questioning suspects and/or witnesses)
検討： けんとう？・ a review or inquest (means that a panel of experts are discussing among themselves, rather than a superior person interrogating an inferior person).
検索：けんさく： internet search
診断 しんだん : medical examination
I DON'T KNOW THE FOLLOWING 3 SYNYOMS - PLEASE HELP;
検索 kensaku /