Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hang dien » quang dien, dang dieu, sang dieu
nhan dien » nhan vien, nhan dieu, nhan dan
su triet » su viet, su tien, ve triet
hieu va » lieu va, hieu qua
cau duc » cao duc, cau luc, chu duc
sach ky » sac ky, sach y, sach ty
hanh de » hanh ve, hanh kem
va cau » van cau, va cac, va dau
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ky nang o hoi. hieu va cau duc va ((hanh de) or (((hang dien) OR (nhan dien)))) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky nang o hoi. hieu va cau duc va ((hanh de) OR (((hang dien) OR (nhan dien)))) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky nang o hoi. hieu va cau duc va ((hanh de) or (((hang dien) OR (nhan dien)))) su triet".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang o hoi. hieu va cau duc va ((hanh de) or (((hang dien) OR (nhan dien)))) su triet*.