Perhaps you should try some spelling variations:
thuat sac » thuat sach, thuat san, thuat tac
lam truoc » lam thuoc, nam truoc, lam truong
truoc ban » truoc bang, thuoc ban, truc ban
hieu van » hieu va, thien van, hieu ve
ban hanh » ban hang
hoc viet » hoc hien
nang xa » nang x, lang xa, nang ma
sac ky » cac ky, sai ky
vi hoc » li hoc, va hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sac ky nang xa hoi. ((hieu van) or (lieu va)) lam truoc ban hanh vi hoc viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sac ky nang xa hoi. ((hieu van) OR (lieu va)) lam truoc ban hanh vi hoc viet.
• Adding a wildcard symbol may retrieve word variants: thuat sac ky nang xa hoi. ((hieu van) or (lieu va)) lam truoc ban hanh vi hoc viet*.