Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nang dieu » dang dieu, sang dieu, bang dieu
dieu cua » dieu tra
vu sach » vu bach, su sach, vu khach
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
tuc va » thuc va, truc va, duc va
ve cam » ve cham, ve cac, va cam

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) or (thuoc sach)) ky dang xa hoi. hieu ve cam ((tuc va) OR (tuc xa)) nang dieu cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (thuoc sach)) ky dang xa hoi. hieu ve cam ((tuc va) OR (tuc xa)) nang dieu cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu sach) or (thuoc sach)) ky dang xa hoi. hieu ve cam ((tuc va) OR (tuc xa)) nang dieu cua tre".
• Adding a wildcard symbol may retrieve word variants: ((vu sach) or (thuoc sach)) ky dang xa hoi. hieu ve cam ((tuc va) OR (tuc xa)) nang dieu cua tre*.