Perhaps you should try some spelling variations:
trong tan » trong quan, trong cac, trong ca
chi sach » chinh sach, chieu sach, co sach
trinh va » trinh van, trinh vat, trinh ve
trinh he » trinh han, trinh hoa, trinh thi
tan phan » toan phan, than phan, van phan
phan lap » phan dau
doi chi » doi khi

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi chi sach - canh ((trinh va) or (trinh he)) dung trong tan phan lap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chi sach - canh ((trinh va) OR (trinh he)) dung trong tan phan lap.
• Adding a wildcard symbol may retrieve word variants: doi chi sach - canh ((trinh va) or (trinh he)) dung trong tan phan lap*.