Perhaps you should try some spelling variations:
"CADTH optimal coarse reports" » "CADTH optimal care reports", "CADTH optimal core reports", "CADTH optimal sparse reports", "CADTH optimal false reports"
cadth optimal » path optimal, width optimal, health optimal
"CADTH optimal case reports" » "CADTH optimal care reports", "CADTH optimal cash reports", "CADTH optimal class reports", "CADTH optimal case report"

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"CADTH optimal case reports\") OR (\"CADTH optimal coarse reports\"))*".
• Removing quotes may allow a broader search: (( CADTH optimal case reports ) OR ( CADTH optimal coarse reports ))*.