Perhaps you should try some spelling variations:
"la integral formulation" » "la lineal formulacion", "e integral formulation", "de integral formulation", "et integral formulation"
"_ integral formulation" » "_ lineal formulacion", "e integral formulation"
"en lineas formulacion" » "en lineal formulacion", "en la formulacion", "en una formulacion", "en linea formulacion", "de lineas formulacion", "y lineas formulacion"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("la integral formulation") OR ("_ integral formulation"))) OR ("en lineas formulacion"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"la integral formulation\") OR (\"_ integral formulation\"))) OR (\"en lineas formulacion\"))".
• Removing quotes may allow a broader search: (((( la integral formulation ) OR ( _ integral formulation ))) OR ( en lineas formulacion )).
• Adding a wildcard symbol may retrieve word variants: (((("la integral formulation") OR ("_ integral formulation"))) OR ("en lineas formulacion"))*.