Perhaps you should try some spelling variations:
qua cham » qua hai, qua cac, va cham
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
xuc van » luc van, vuc van, xuc ban
duc van » duc va, duc tan, duc manh
hanh di » hanh vi, hanh de, hang di
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: tu sach y ((nang xa) OR (nang ma)) hoi. hieu qua cham ((xuc van) or (duc van)) hanh di cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (nang ma)) hoi. hieu qua cham ((xuc van) OR (duc van)) hanh di cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang xa) OR (nang ma)) hoi. hieu qua cham ((xuc van) or (duc van)) hanh di cua viet*".