The Library assigns subject headings to all items in COAST. You can use these subject headings to find similar items on the same topics. If you find a good book in COAST, check out the subject headings. 
Library of Congress Sub-Headings
The Library assigns subject headings to all items in COAST. You can use these subject headings to find similar items on the same topics. If you find a good book in COAST, check out the subject headings.
You can add common sub-headings to your keywords (your keyword + common sub-heading). Such as:
For example, a KEYWORD search on alcohol and health will give you over 100 items but a SUBJECT search on alcohol and health will give you about 4 items.