I must completely disagree with the other posters claiming that keyword searches are not useful. For niche research, they are extremely helpful or even necessary. Google and Bing have reached the point where it is impossible to do real, niche academic research on them. For instance, I had a very specific thing I was trying to look up involving medicine, religion, and Marco Polo.
Try searching for "marco polo doctors" on Google and witness it giving very counterintuitive, one-sided results that may align with the current zeitgeist of interest from people searching Google, but diverge completely with the aim of literal, precise keyword search needed by academics. I did work to improve or hone the search down, looking up Kublai Khan, doctors, atheism brings up blogspam articles on doctors and atheism, but scant results on the 13th century Mongol emperor's religious medical interest. Trying to narrow the search further by including variations on Cambulac, Cambaliech, trying to find any info beyond surface-level on John of Montecorvino and his retinue... all is impossible with search engines in 2018.