Identify the main concepts within your topic.
Finding useful sources is highly dependent upon the words you choose to use in your searching.
Academic Search Premier - this database is very multidisciplinary and may include articles on some aspects of bioresource sciences. Some of the journals included are available in full-text.
CAB Abstracts - this database covers agricultural, forestry, nutrition and veterinary medicine
Medline - covers medical topics and much basic science research in areas including toxicology, microbiology, molecular biology and more, coverage is back to 1950
Agricola - covers agricultural topics, including entomology, plant sciences, horticulture and food science, coverage is back to 1970.