Think much about something vs Think much of something

think much about something—have the mind preoccupied with smth.:

• No one had taught her this, but she was a woman who thought much about God.

think much of something—

1. = think much about something:

• He thought much of the evils of the journey for her, and not a little of the fatigues of his own horses.

2. (usually negat.) regard smth. as important; value or esteem smth. highly:

• He gives very good dinners, but I don’t think much of his cellar.