In addition to using the Advanced Search form in Scholar, it is possible to directly enter search syntax into the Search box in Scholar. The format for this, with examples, is provided below:

Search Arguments can be any of the following string prefix:string "string" prefix:"string" e.g.
discipline:Nursing 
discipline:"Nursing"

Search arguments can be concatenated with spaces in between to achieve AND results: prefix:string1 prefix:string2 i.e. this is equivalent to "prefix:string1 AND prefix:string2". e.g.
inst:"Grand Rapids Community College" discipline:Nursing

Also, arguments can be grouped by parentheses, which means that between groups of parens, there is an OR operation:
(prefix:string1 string2) (string3) (prefix:"string4" "string5") is equivalent to (prefix:string1 AND string2) OR (string3) OR (prefix:"string4" AND "string5") e.g.
(inst:"Grand Rapids Community College") (discipline:Nursing)

Valid prefixes:
"tag" (freeform tags) e.g. tag:surgery  tag:"arthurian studies"
"discipline" (discipline tags) e.g. discipline:Nursing  (Note: 1st character of disciplines must be Capitalized)
"course" (course tags) e.g. course:"BIOL220-01: Introductory Oceanography 01-BIOL227-01" (Note: you must be a member of the course for a course search to work)
"user" (beyond username) e.g. user:ekunnen
"inst" (institution) inst:"Grand Rapids Community College" (Note: 1st character of institution names must be Capitalized)
"role" (course role) e.g. role:instructor