Perhaps you should try some spelling variations:
thuat sach » thuat lanh
thuat san » thuat toan, thuat song, thuat lanh
hang dien » quang dien, dang dieu, nhan dien
cau duc » cao duc, cau luc, chu duc
hanh de » hanh ve, hanh kem
su viet » so viet
hieu va » lieu va, hieu qua
nang o » nang co, nang ho, nang ro
va cau » van cau, va cac, va dau
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) OR (thuat san)) ky nang o hoi. hieu va cau duc va ((hanh de) or (hang dien)) su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuat sach) OR (thuat san)) ky nang o hoi. hieu va cau duc va ((hanh de) OR (hang dien)) su viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuat sach) OR (thuat san)) ky nang o hoi. hieu va cau duc va ((hanh de) or (hang dien)) su viet".
• Adding a wildcard symbol may retrieve word variants: ((thuat sach) OR (thuat san)) ky nang o hoi. hieu va cau duc va ((hanh de) or (hang dien)) su viet*.