關鍵字是最常用的檢索策略，可以利用單字或辭彙找到在書刊名、篇名或其他欄位中出現相同辭彙的資料。關鍵字會影響搜尋出來的資料，在搜尋引擎中輸入2~3個關鍵字會比直接輸入一句話或是一個問題，更容易找到相關的查詢結果。

閱讀文章時，如何找出該篇文章關鍵字，可以參考：

• 經常出現的名詞

• 標題裡的名詞

• 有被特別介紹的名詞

• 感覺是這篇文章裡面重要的名詞

• 看不懂、覺得很特別的名詞

The first strategy in effective research is to start with a basic keyword search of your topic. Typing a complete sentence or question into a search box, will not give you as comprehensive or relevant results as just entering the two or three keywords that best reflect your question.

When reading an article, how to identify its keywords:

• Nouns that frequently appear.

• Nouns in the title.

• Nouns that are specially introduced.

• Nouns that seem important within the article.

• Unfamiliar or intriguing nouns.

假設想研究的主題與狗有關，可以先列出與狗有關的詞，包括廣義詞、同義詞、狹義詞等，不僅能查到更多資料，在過程中也更清楚自己想探究的是什麼。
Assuming that the topic you want to research is related to dogs, you can first list the words related to dogs, including broad words, synonyms, narrow words, etc. Not only can find more information, but also know more clearly what you want to explore in the process.

萬一今天查到的資料很多，你可以加上限縮條件，這樣查詢結果不僅會變少，也更符合你的需求。

1. 布林邏輯
   AND：以And連結的關鍵字要同時出現，才會成為查詢結果。Google或部分搜尋引擎會把空格視為AND。
   OR：以OR將所有同義詞連起來，以確保想查詢的資料沒有闕漏。
   NOT：從查詢結果中排除掉某個關鍵字的資料結果。Google或有些搜尋引擎會會把減號-視為NOT。

2. 引號
   如果在網路行銷前後加入引號，用"網路行銷"進行搜尋。搜尋引擎會把這四個字當做一個詞來查詢，不會拆開來分別查詢「網路」與「行銷」。 

3. 萬用字元

• *： 可以查出所有字首或字尾相同之關鍵字，例如 Depress* 結果會包含depress, depressive, depressor……

• # ：關鍵字有一個字母不確定或單複數變化，例如 wom#n 結果會包含woman、women 

• ? ：美式與英式英文的差異或不確定關鍵字是否包含該字母，例如colo?r 結果會包含 color, colour

In case a lot of information is found today, you can add limiting conditions, so that the query results will not only be smaller, but also more in line with your needs.

1. Boolean logic
   AND: Keywords linked by And must appear at the same time to become query results. Google or some search engines treat spaces as AND.
   OR: Use OR to connect all synonyms to ensure that there are no gaps in the information you want to query.
   NOT: Exclude the data results of a certain keyword from the query results. Google or some search engines will treat the minus sign - as NOT.

2. Quotation marks
   If you add quotation marks before and after Internet marketing, search with "Internet marketing." Search engines will treat these four words as one word for query, and will not separate them to query "network" and "marketing" separately.

3. wildcards

• *: Can find all keywords with the same beginning or suffix, for example, Depress* The result will include depress, depressive, depressor...

• #: The keyword has one letter that is uncertain or singular or plural. For example, wom#n results will include woman, women

• ?: The difference between American and British English or whether the keyword contains this letter, for example, colo?r The result will contain color, color

許多學術文章是站在巨人的肩膀上，參考了前人所撰寫的文章，加上自己的觀點、論證與結論而成。當你在查詢資料時，可以發現較為嚴謹的資料來源，都會列出參考文獻。「文獻滾雪球」就是留意文章的參考文獻或是它被哪些文章引用，透過這個方法可以找到更多相關主題的資料。

Many academic articles are built upon the work of predecessors, referencing previously written papers, and adding their own perspectives, arguments, and conclusions. When you search for information, you can find more rigorous sources that list references. "Literature snowballing" involves paying attention to the references of articles or which articles cite it, allowing you to find more information on related topics through this method.

參考來源

•  Choosing and Using Sources: A Guide to Academic Research 

• 全國高級中等學校圖書館輔導團「圖書館引導學生自主學習參考手冊」

• http://apps.webofknowledge.com/WOS_GeneralSearch_input.do?product=WOS&search_mode=GeneralSearch&SID=D4HaF1R5X2zyKTSehXE&preferencesSaved=&editions=SSCI