Perhaps you should try some spelling variations:
van pham » san pham, van phan, van phat
hieu van » hieu va, thien van, lieu va
han tai » hang tai, nhan tai, van tai
so sach » so sanh, bo sach, co sach
tu nong » tu dong, tu cong, tu tuong
tu tong » tu tuong, tu trong, tu dong
va han » va phan, van han, va hanh
cua tu » cua tuc, cua su, cua cu
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ((tu nong) OR (tu tong)) x hoi. hieu van pham duc va han tai ((cua te) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((tu nong) OR (tu tong)) x hoi. hieu van pham duc va han tai ((cua te) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((tu nong) OR (tu tong)) x hoi. hieu van pham duc va han tai ((cua te) or (cua tu))".
• Adding a wildcard symbol may retrieve word variants: so sach ((tu nong) OR (tu tong)) x hoi. hieu van pham duc va han tai ((cua te) or (cua tu))*.