Possible Clues:

• Turn upside down in Zinfandel vessel
• Search for information
• Conduct exhaustive research (into)
• Go (into)
• I can't get into 'To be or not to be' options -- dig?
• Search deeply (into)
• Leaders of life-saving volunteers go into river and probe deeply
• Model very content during search
• Dig — investigate
• Burrow, rummage