@yuyang.1958You typically don't need to use quotes around keywords. Try
ek.get_news_headlines("Product:IFRFM AND Topic:ISU AND Topic:EUB AND (PRICED OR DEAL)")
ek.get_news_headlines("Topic:ISU AND Topic:EUB AND (PRICED OR DEAL)")
"Topic:ISU AND Topic:EUB AND (\\\"PRICED\\\" OR \\\"DEAL\\\")"
r"Topic:ISU AND Topic:EUB AND (\"PRICED\" OR \"DEAL\")"
But as I said at the beginning the easiest is to not include keywords in quotes at all.
This query is a duplicate of the one in this comment.