Search string may contain the logical operators AND and OR and the operands () and "". AND searches for both words or phrases, while OR searches for one or the other. If the search string uses AND and OR at the same time, the AND operation takes priority, unless you enclose the OR operation in parentheses, as in (A or B) and C. To find an exact phrase, such as "current price", enclose the phrase in quotes.
Please refer to the following examples:

• Search for Nigeria to find all series that contain Nigeria.
• Search for GDP or expenditure to find all series that contain either GDP or expenditure indicators.
• Search for GDP and expenditure to find all series that contain both GDP and expenditure indicators.
• Search for (GDP or expenditure) "current price" to find all series that contain either GDP or expenditure indicators or the phrase "current price".