Perhaps you should try some spelling variations:
thuat sac » thuat sach, thuat tac, thuat mach
lam truoc » lam thuoc, nam truoc, lam truong
thuat san » thuat toan, thuat song, thuat lanh
truoc va » truc va, thuoc va, truong va
va dinh » van dinh, va kinh, va tinh
dai hoa » dai khoa, dai hoc, dai hoi
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
di hoa » doi hoa, do hoa, bi hoa
va lam » van lam, va lap

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) or (thuat san)) ky nang xa hoi. hieu va lam truoc va dinh ((di hoa) OR (dai hoa)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuat sac) OR (thuat san)) ky nang xa hoi. hieu va lam truoc va dinh ((di hoa) OR (dai hoa)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuat sac) or (thuat san)) ky nang xa hoi. hieu va lam truoc va dinh ((di hoa) OR (dai hoa)) viet".
• Adding a wildcard symbol may retrieve word variants: ((thuat sac) or (thuat san)) ky nang xa hoi. hieu va lam truoc va dinh ((di hoa) OR (dai hoa)) viet*.