Modern hiv tests should detect stable genomes of the virus that do not change over generations. so they can detect all strains of hiv. is it true? pls help?

There are a few kinds of HIV test. Most detect all variants of the virus, but some may miss some uncommon variants. However, some combination of tests can detect infection with identify all types and strains. Your health department (national or provincial?) probably will know whether there are believed to be variants in your geographic area that might requires special testing. Good luck.