Here are the Google search operators that you can use to make better searches inside Google custom search.
List of Google Search Operators

“OR or |“- example- “Microsoft OR google”
AND example- “Microsoft AND google”
NOT or “-“
Exclude certain text from search results- For Example, “USA -Florida” to exclude search results from all over the USA but excluding text that contains Florida
” “– Search for exact phrase matches-For example, “data now”
site: search within a specific site.Example- site:expertrec.com custom
INURL– for example inurl:expertrec
INTITLE: Searches within the title of the search results
INTEXT– Searches within the snippet of the search results
Filetype: search for specific filetypes only
( )
Group multiple terms or search operators to control how the search is executed.
Example: (ipad OR iphone) apple
$
Search for prices. Also works for Euro (€), but not GBP (£) 🙁
Example: ipad $329
define:
A dictionary built into Google, basically. This will display the meaning of a word in a card-like result in the SERPs.
Example: define:entrepreneur
cache:
Returns the most recent cached version of a web page (providing the page is indexed, of course).
Example: cache:apple.com