Perhaps you should try some spelling variations:
ve triet » va trien
cac thuc » cach thuc, cac thu, can thuc
su triet » su viet, su tien
hang doi » hang di, hang loi, huong doi
hang don » hang ton, dang don, hang do
thuc van » thuc vat, thuc dan, thuc va
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
vu sach » vu bach, su sach, vu khach
ve cac » va cac, vien cac
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang

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

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