I want to search for papers with this criteria : the title contains preeclampsia OR the title contains toxemia and the text contains pregnan*.
I used this:
intitle:preeclampsia OR (intitle:toxemia AND intext:pregnan*) 489 hits
But google scholar didn't understand the parenthesis and gave the same results as this:
intitle:preeclampsia OR intitle:toxemia AND intext:pregnan* 489 hits