Perhaps you should try some spelling variations:
nang phap » nang phat, nang phan, ban phap
hanh than » hanh han, hanh nhan, hanh phan
nang cai » nang cao, nang tai, nang can
nang cap » nang cao, nang cham, hang ca
than cua » nhan cua, thai cua, ban cua
cua viet » ca viet, hoa viet, cua vat
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
cho hoc » co hoc, khoa hoc
va hanh » van hanh, va thanh, va danh
va cho » van cho, va co, va che

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky ((nang cai) or (((nang cap) OR (nang phap)))) hoi. lieu va cho hoc va hanh than cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky ((nang cai) OR (((nang cap) OR (nang phap)))) hoi. lieu va cho hoc va hanh than cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky ((nang cai) or (((nang cap) OR (nang phap)))) hoi. lieu va cho hoc va hanh than cua viet".
• Adding a wildcard symbol may retrieve word variants: vu sach ky ((nang cai) or (((nang cap) OR (nang phap)))) hoi. lieu va cho hoc va hanh than cua viet*.