Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
dieu tra » dieu tri, dieu cua
thuc dan » thuc hanh, hoc dan, thuc vat
tu sach » thu sach, te sach, tu cach
hiem ve » nhiem ve, hieu ve, hiem xe
dang ho » dang do, dong ho, dang ha
ky dang » ky nang, ky danh
su sach » so sach, vu sach
ho hoi » hoc hoi, hoa hoi, hoi hoi
ve am » va am

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (su sach)) ky dang ho hoi. hiem ve am thuc dan thanh ((dieu tra) or (kiem tra)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky dang ho hoi. hiem ve am thuc dan thanh ((dieu tra) OR (kiem tra)) tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky dang ho hoi. hiem ve am thuc dan thanh ((dieu tra) or (kiem tra)) tre*.