In principle it is allowed for words to contain blanks. Tables show the most frequent multiwords containing 1, 2, 3 or 5 blanks.
This can be used to put proper names or phrases into the wordlist. But, this is not done automatically.
For one blank:
select w_id-100,freq, word from words where w_id>100 and word like "% %" limit 10;
3.12.1 Words with Hyphens
3.12.3 (Multi-)Words with dots
3.12.4 Words containing special characters