Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cua viet » ca viet, hoa viet, cua vat
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
sach ky » sac ky, sach y, sach kem
va xanh » va hanh, va anh, va banh
va danh » va dinh, va dan, va hanh
van cau » van dau, van hau, van chat
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) or (sach ty)) nang xa hoi. hieu van cau truc ((va xanh) OR (va danh)) di cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sach ty)) nang xa hoi. hieu van cau truc ((va xanh) OR (va danh)) di cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sach ty)) nang xa hoi. hieu van cau truc ((va xanh) OR (va danh)) di cua viet*".