Thematic words are more likely to be included in the index. Common words, like those indicated, may have been excluded from the indexing procedure.
Specific searches tend to be faster.
It is better to make your search as specific as possible. Indexing is in most cases based on the words in all the names associated with a profile, and rarely with words in the body of the text. Take note of the red comments to the search results. To simplify the presentation of search results, or of any profile, turn options to their default values. As a registered user, your options are saved as preferences between sessions.