Recently i used VOS viewer for generating a networked keyword mapping based on the literature extracted from the Academic Search Engines (ASE's) and Academic Databases (AD's) related to innovations in Offsite Construction. For the difference in ASE's and AD's you may follow this link: https://www.researchgate.net/post/What_is_the_difference_between_Academic_Search_Engine_and_Academic_Database?isAnswerFieldFocused=true

First of all you need to go to the ASE's and AD's to identify relative to your scope literatures and then downloading them in .RIS format. Assuming that you have already in stalled VOS viewer you then goto the "Create" tab and choose "Read data from reference managers files". Select the downloaded RIS files from the ASE's and AD's and click "Next". Choose the "Type of Analysis" and "Counting Method" followed by adjusting the threshold for keyword meeting criteria. Chhose the number of keywords later followed by Keyword verification. In result to these actions you will observe the Keyword mapping charted on the screen in VOS GUI. From the analysis tab you can always change Normalization, Layout, Clustering, Visualization, Labels, Lines, and Colour Variations.

Be kind to share anyother such platform that you have used or plan to use !