in the keyword search settings, the OR separator is a space, the AND separator is a comma, and the encapsulation character is a quote.
this means if you search for:
Line 1 wash
it will look for:
Field Contains "Line" OR Field Contains "1" OR Field Contains "wash"
you say you want to return:
Any product that contains both "line 1" and "wash".
so in the search field you will need to enter the search phrase as:
"line 1", wash
you need the quotes around line 1 to encapsulate the term, you need the comma to force it to use AND so it will search for:
Field Contains "Line 1" AND Field Contains "wash"