There are two places for the date range when searching both Academic Search Complete and PsycARTICLES. It does not matter which database you choose first. In this FAQ, Academic Search Complete was chosen first and then PsycARTICLES chosen second.
For the advanced search options, the ones that will be applied to both databases will be found at the top. That is where to click the Full Text and Scholarly (Peer Reviewed) Journals.
That is also the Publication Date boxes to use.
Here are the advanced search options for Academic Search Complete which are listed right below the general ones.
And here are the advanced search options listed for PscyARTICLES at the bottom of the page. A search was done by putting in 2000 and 2005 in just these boxes which brought back 105, 752 items in the results list. By using the year of publication boxes at the top of the advanced search options brought back 21,563 items in the results list. When both year of publication boxes were used (the one at the top and the one for PsycARTICLES) the number of results I get is 21,563.
When only the publication date box for PsycARTICLES is used, on the results page it shows it is limited to Year of Publication (highlighted below) but, the actual Publication Date range used is not what was put into the advanced search options for PsycARTICLES which seems to mean that the publication dates of 2000 - 2005 was only applied to the one database but the all dates available were searched in the other database.
When only the publication date boxes at the top of the screen are used, it looks like the dates are applied to both databases.
So, use the boxes at the top of the advanced search page so that only articles from 2000-2005 are looked at from both databases.
When I use the publication date boxes at the top of the screen, it looks like the dates are applied to both databases.