How to include 2 words within Regex and result must be based on only those 2 words VB.NET - regex

Question

I would like to know how to include only 2 or more keywords within a Regex. and ending results should only show those words defined, not only one word.
What I currently have works with multiple keywords but I want it to use BOTH words not either one of the other.
For example:
Dim pattern As String = "(?i)[\t ](?<w>((arma)|(crapo))[a-z0-9]*)[\t ]"
Now the code works fine by including 'arma' or 'crapo'. I only want it to include BOTH 'arma' AND 'crapo' otherwise do not show any results.
Dealing with finding certain keywords within a PDF document and I only want to be shown results if the PDF document includes BOTH 'arma' and 'crapo' (Works fine by showing results for 'arma' OR 'crapo' I want to see results based on 'arma' AND 'crapo'.
Sorry for sounding so repetitive.
Edit: Here is my code. Please read comment.
Dim filesz() As String = GetPatternedFiles("c:\temp\", New String() {"tes*.pdf", "fes*.pdf", "Bas*.pdf"})
'The getpatterenedfiles is a function" also gettextfromPDF is another function.
For Each s As String In filesz
Dim thetext As String = Nothing
Dim pattern As String = "(?i)[\t ](?<w>(crapo)|(arma)[a-z0-9]*)[\t ]"
thetext = GetTextFromPDF(s)
For Each m As Match In Regex.Matches(thetext, pattern)
ListBox1.Items.Add(s)
Next
Next

Answer 1

You can use this regex:
\barma\b.*?\bcrapo\b|\bcrapo\b.*?\barma\b
Working demo
The idea is to match arma whatever crapo or crapo whatever arma and use word boundaries to avoid words like karma.
However, if you want to match karma or crapotos as you asked in your comment you can use:
arma.*?crapo|crapo.*?arma