Perhaps you should try some spelling variations:
nang noi » nang doc
nang doi » nang doc, hang doi, nang dong
lang van » dang van, tang van, hoang van
tu sach » thu sach, su sach, te sach
cac tuc » cac toc, cac tu, cac tac
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay
ve cac » va cac, vien cac
thiet » thieu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky ((lang xa) or (lang van)) hoi. hieu ve cac tuc xa ((nang doi) or (nang noi)) va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((lang xa) OR (lang van)) hoi. hieu ve cac tuc xa ((nang doi) OR (nang noi)) va thiet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((lang xa) or (lang van)) hoi. hieu ve cac tuc xa ((nang doi) or (nang noi)) va thiet*.