When using vim's help I can jump to multi-word tags, but when creating my own tags Ctrl-] tries to match individual words. Consider the following example:
When pressing Ctrl-[ over "a" it tries to match "a" and not "a-tag". Similarly, if the cursor is on top of "tag" vim searches for "tag" only. When visually selecting "a-tag" it works.
The tags file is the following:
a-tag file.txt /*a-tag*