Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
thi hang » thi hanh, thi nang, thi hong
van hanh » van thanh, ban hanh, van anh
thuc van » thuc vat, thuc dan, thuc va
su sach » so sach, vu sach
da thuc » dan thuc, dai thuc, dam thuc
vien da » vien dai, hien dai
ty hang » ly hang, ty xang, thu hang
ty nang » ky nang, ty xang, ly nang
vi cua » vai cua, di cua
cua te » cua tu

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 ((ty nang) or (((ty hang) OR (thi hang)))) xa hoi. hieu vien da thuc van hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty nang) OR (((ty hang) OR (thi hang)))) xa hoi. hieu vien da thuc van hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ty nang) or (((ty hang) OR (thi hang)))) xa hoi. hieu vien da thuc van hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((ty nang) or (((ty hang) OR (thi hang)))) xa hoi. hieu vien da thuc van hanh vi cua te*.