Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
pham duy » pham duc
sach tu » cach tu, sach ty, sach uu
nang xa » nang x, lang xa, nang ma
duy may » duy mai, dung may, duy thay
di cua » doi cua, de cua, do cua

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 tu) or (sach thu)) nang xa hoi. hieu van pham duy may tinh ((di cua) OR (dai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach tu) OR (sach thu)) nang xa hoi. hieu van pham duy may tinh ((di cua) OR (dai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach tu) or (sach thu)) nang xa hoi. hieu van pham duy may tinh ((di cua) OR (dai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach tu) or (sach thu)) nang xa hoi. hieu van pham duy may tinh ((di cua) OR (dai cua)) triet*.