Perhaps you should try some spelling variations:
sau tien » dau tien, su tien, cau tieng
loai sau » loai san, loai su, loai sach
dan loai » dang loai, phan loai, nhan loai
nam thuc » nam thuoc, am thuc, nam thu
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
ky lang » ky dang, ky tang, tay lang
cam tuc » cam xuc, cam tu, dam thuc
va dan » ca dan, va dao, va dau

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) or (ky nang)) xa hoi. hieu ve ((cam tuc) OR (nam thuc)) va dan loai sau tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky nang)) xa hoi. hieu ve ((cam tuc) OR (nam thuc)) va dan loai sau tien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky lang) or (ky nang)) xa hoi. hieu ve ((cam tuc) OR (nam thuc)) va dan loai sau tien".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) or (ky nang)) xa hoi. hieu ve ((cam tuc) OR (nam thuc)) va dan loai sau tien*.