Different search results if fulltext searching on one or two lines?

[Caroline Armitage]

Hi,

I was wondering if anyone could shed any light on this issue. Not sure if I am overlooking something obvious...

I am getting different numbers of results for a search depending if it is on one or split over two lines in the web interface (or even the API). Test searches:

Web interface 1 line search in fulltext = 11810 results

https://openalex.org/works?page=1&filter=default.search%3A%22cat%22%20AND%20%22gerbil%22

Web interface two line search in fulltext = 11900 results

https://openalex.org/works?page=1&filter=default.search%3A%22cat%22,default.search%3A%22gerbil%22

The API search gives 11812 results

https://api.openalex.org/works?search=(cat%20AND%20gerbil)

We discovered this while building a real search, where the 1-line search results contained 1 unique result, and the 2-line search contained 5 unique results (i.e. it is not only that one search is finding more; they are finding different results). We looked at the differing documents - all of the documents that differed between the searches contained the relevant terms.

Any thoughts or explanations are appreciated!

Caroline