client/lib/domains/index.js
function getDomainSuggestionSearch( search, minLength = 2 ) {
	const cleanedSearch = getFixedDomainSearch( search );

	// Ignore any searches that are too short
	if ( cleanedSearch.length < minLength ) {
		return '';
	}

	// Ignore any searches for generic URL prefixes
	// getFixedDomainSearch will already have stripped http(s):// and www.
	const ignoreList = [ 'www', 'http', 'https' ];
	if ( includes( ignoreList, cleanedSearch ) ) {
		return '';
	}

	return cleanedSearch;
}
function getDomainSuggestionSearch( search, minLength = 2 ) {
	const cleanedSearch = getFixedDomainSearch( search );

	// Ignore any searches that are too short
	if ( cleanedSearch.length < minLength ) {
		return '';
	}

	// Ignore any searches for generic URL prefixes
	// getFixedDomainSearch will already have stripped http(s):// and www.
	const ignoreList = [ 'www', 'http', 'https' ];
	if ( includes( ignoreList, cleanedSearch ) ) {
		return '';
	}

	return cleanedSearch;
}
/*
Given a search string, strip anything we don't want to query for domain suggestions

@param {string} search Original search string
@param {integer} minLength Minimum search string length
@return {string} Cleaned search string