Perhaps you should try some spelling variations:
dich hoc » sinh hoc, hinh hoc, tinh hoc
vu sach » vu bach, su sach, vu khach
ly lang » ly hang, ly vang, ly lanh
le lang » le tang, le dang, le xang
hieu va » lieu va
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
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: vu sach ((ly lang) OR (le lang)) xa hoi. ((hieu va) or (hieu qua)) cac tuc van dich hoc cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ((ly lang) OR (le lang)) xa hoi. ((hieu va) OR (hieu qua)) cac tuc van dich hoc cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ((ly lang) OR (le lang)) xa hoi. ((hieu va) or (hieu qua)) cac tuc van dich hoc cua te".
• Adding a wildcard symbol may retrieve word variants: vu sach ((ly lang) OR (le lang)) xa hoi. ((hieu va) or (hieu qua)) cac tuc van dich hoc cua te*.