# 布尔运算符

可以在搜索面板多个搜索式(行)之间使用布尔运算符 And, Or,和 Not，效果如下：

* **AND** 是查找同时符合当前搜索式和下面一行搜索式的文献，AND 可以减少搜索结果数量。

**例：**搜索 howsci AND website 同时搜索符合这两条搜索词的文献

* **OR** 可满足当前搜索式，也可以满足下面搜索式，两都满足其一即可。OR 可以增加搜索结果数量。

**例：**搜索 howsci OR website 的会查找满足这两个条件其中一个或者两个的文献。

* **NOT** 查找符当前搜索式，但是不包括下面的搜索式的文献。NOT 减少搜索结果数量。

**例：**搜索 howsci NOT website 只搜索满足 howsci 但是不包括 website 的文献

可在最多**9个**搜索行之间使用布尔运算符(AND, OR NOT)

[EndNote](http://www.howsci.com/tag/endnote/) 的复合搜索是从上往下逐步进行的，比如在搜索面板中有4行搜索，[EndNote](http://www.howsci.com/tag/endnote/) 先进行前两个布尔运算，然后结果再和第3个布尔运算符进行结合得出结果，最后再和第4个进行结合最后得出结果。


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