Perhaps you should try some spelling variations:
thien van » thi van
trinh dai » trinh tai, trinh di, trinh da
nam thuc » nam thuoc, am thuc, nam thu
luat tuc » luat thue
va trinh » van trinh, va tinh, lap trinh
so sach » so sanh, bo sach, co sach
nang so » nang som, nang co, nang su
nang ho » nang hoc, nang co, tang ho
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: so sach y ((nang so) or (nang ho)) hai. thien van ((nam thuc) or (luat tuc)) va trinh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((nang so) OR (nang ho)) hai. thien van ((nam thuc) OR (luat tuc)) va trinh dai cua te.
• Adding a wildcard symbol may retrieve word variants: so sach y ((nang so) or (nang ho)) hai. thien van ((nam thuc) or (luat tuc)) va trinh dai cua te*.