Perhaps you should try some spelling variations:
sach thue » sach thu, sach thieu, sach tham
va triet » va thiet, va trien, ve triet
tinh doi » trinh doc, trinh do, tinh hoc
duy mai » duy ai, duy thai
duy may » dung may, duy thay
nang xa » nang x, lang xa, nang ma
sach ty » sach y, sach tu, sach thu
hieu v » hieu va, hieu ve, hieu 2
doi va » hoi va, noi va, dai va
v pham » vi pham, d pham

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 thue) or (sach ty)) nang xa hoi. hieu v pham ((duy may) or (duy mai)) tinh doi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thue) OR (sach ty)) nang xa hoi. hieu v pham ((duy may) OR (duy mai)) tinh doi va triet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach thue) or (sach ty)) nang xa hoi. hieu v pham ((duy may) or (duy mai)) tinh doi va triet*.