On the search screens you see several blank colored entry fields, the use of which is explained here.
You can use these fields separately or in combination. For example, if you enter the name ‘Diener’ in the author field, a long list of publications of this productive author will appear below the green colored search screen. If you also enter the keyword ‘income’ in the field for word(s) in the title, that list will be reduced to publications on happiness and income by this author.
Likewise, you can condense initial selections of publications by period (in years) and by source, such as a journal. If you enter the word ‘economic’ in the source field, the selection will limit to publications that appeared in journals or books with the word ‘economic’ in their title.
In the same vein, you can select measures of happiness and research findings using the various ‘filters’ you can select on the search screen.