Searching for a word in a list of tuple extracted from a db via SQL
You could try doing the filtering at the database level. Something like:

sql = "SELECT COUNT(*) FROM mydata WHERE myTextColumn MATCH %s"
for word in wordList:
    db = cursor.execute(sql, word).fetchall()
    dicoVolume[word] = db[0][0]


This would have the same word boundary caveats mentioned by Ludisposed, but it would save retrieving the entire table. Whether it's faster will probably depend on the relative sizes of the table and the word list, and if the column has an index it can use.

Edit: To use full text indexes with SQLite, it seems you need to create the table as an FTS table, and then do your searches using the MATCH command:

CREATE VIRTUAL TABLE mydata USING fts3(content TEXT);
INSERT INTO mydata VALUES ('some test data');
SELECT count(*) FROM mydata WHERE content MATCH 'test';


SQL Fiddle: http://sqlfiddle.com/#!7/fd6c5/8