Perhaps you should try some spelling variations:
quantitative observations » quantitative observation, qualitative observation, quantitative conservation
observations programs » observation programs, conservation programs, observations problems
microarray chips » microarrays chip, microarray cross, microarray rip
microarray chip » microarray cgh, microarrays case, microarrays cell

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: "quantitative observations programs https ((microarray chips) OR (microarray chip))~".
• Adding a wildcard symbol may retrieve word variants: quantitative observations programs https ((microarray chips) OR (microarray chip))*.