A DOI can be made resolvable by adding it to the end of the URL https://doi.org/
Try these example DOIs:
10.1007/s00138-017-0825-7
10.1371/journal.pone.0195878
10.1080/01930826.2018.1436778
10.1016/j.acalib.2017.09.003
Using the above URL + the DOI will take you directly to the content. You can also simply enter the DOI into a search box and find the content, though there may be several items displayed.