Perhaps you should try some spelling variations:
operation instrumentation » applications instrumentation, therapy instrumentation, modern instrumentation
instrumentation theory » instrumentation methods, instrumentation https, instruction theory
theory decision » theory design
basic linear » quasi linear, basic life
class linear » less linear, mass linear, class library

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

• Performing a fuzzy search may retrieve terms with similar spellings: operation instrumentation theory decision ((basic linear) or (class linear))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: operation instrumentation theory decision ((basic linear) OR (class linear)).
• Adding a wildcard symbol may retrieve word variants: operation instrumentation theory decision ((basic linear) or (class linear))*.