Perhaps you should try some spelling variations:
day thanh » dao thanh, dat thanh, da thanh
dieu tra » dieu tri, dieu cua
thuc day » thuc dan, thuc vat
tu sach » thu sach, su sach, te sach
hiem he » hiem xe, hieu he, thien he
dang ho » dang do, dong ho, dang ha
ky dang » ky nang, ky danh
so sach » so sanh, bo sach, co sach
ho hoi » hoc hoi, hoa hoi, hoi hoi
he am » he nam, ve 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 (so sach)) ky dang ho hoi. hiem he am thuc day thanh ((dieu tra) or (kiem tra)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (so sach)) ky dang ho hoi. hiem he am thuc day thanh ((dieu tra) OR (kiem tra)) tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (so sach)) ky dang ho hoi. hiem he am thuc day thanh ((dieu tra) or (kiem tra)) tre*.