Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
dang xay » dang van, van xay
tinh oi » tinh doi, tinh toi, tinh voi
va tinh » may tinh
cac tuc » cac toc, cac tu, cac tac
hieu va » lieu va, hieu qua
su sach » so sach
nang xa » nang x, lang xa, nang ma
vu sach » vu bach, vu khach
tuc va » thuc va, truc va, tuc xa
oi su » ki su, vi su

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) OR (vu sach)) ky ((nang xa) or (dang xay)) hoi. hieu va cac tuc va tinh oi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) ky ((nang xa) OR (dang xay)) hoi. hieu va cac tuc va tinh oi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (vu sach)) ky ((nang xa) or (dang xay)) hoi. hieu va cac tuc va tinh oi su triet".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (vu sach)) ky ((nang xa) or (dang xay)) hoi. hieu va cac tuc va tinh oi su triet*.