From the Spell Checker interface, select Suggestions Depth from the Options menu.
Select the value and click OK.
This setting allows you to set the speed and efficiency of the Spell Check. Ranging from 0, the fastest but least efficient, to 100, the slowest but most efficient. The higher you set the value for suggestions depth, the slower but more accurate the search will be.
Setting Spelling Options
Setting the Color for Misspelled Words