"increased their knowledge" is a correct and usable phrase in written English.
It can be used when you are talking about someone gaining knowledge about a topic or subject. For example, "The students increased their knowledge of physics by studying for the final exam."
Through conversation with others who were more knowledgeable about the condition, the informants increased their knowledge.
Students indicated that the course increased their knowledge of pharmacoeconomics.
But universities argue that many international degree students are recruited from non-degree courses, on which they have improved their English and increased their knowledge.
I always hope attendees feel that they have increased their knowledge and skills and developed new business goals, but more importantly, I hope they feel taken care of.
We have shown growers many novel systems, shown them they work (or not!), and increased their knowledge of what is available in the marketplace.
Throughout Kiowa's occupation local stone was used extensively, and over time people increased their knowledge of the local lithic landscape, using more diverse local raw materials.
Preliminary findings indicate that participants were very satisfied with the training, increased their knowledge of issues pertaining to race and racism, and became more aware of racial dynamics.
Out of 103 students for whom I have served as GSI in three different courses during the last two years, 94 stated that the game increased their knowledge of key concepts, helped them identify areas they needed to review, and that they would recommend the game to a friend over traditional question-and-answer review sessions.
Results showed that residents increased their knowledge and performance by synthesizing the content.
They have increased their knowledge beyond the theoretical programme of the subjects, enhancing their academic yield.
Seniors increased their knowledge about quality care and their role in preventing medical errors and highly rated the Websites.
