What is the limitaion of the search box on the top right of LDSD it will pickup Incident numbers, but when I type in a name it errors out. or if i type in the word open it references web docs.

What are the limitations of the search box  on the top right of LDSD it will pickup Incident numbers, but when I type in a name it errors out (The search did not return any results.). or if  I type in the word open it references web docs.