Perhaps you should try some spelling variations:
nang cau » nang cao, hang cau, nang dau
toc sach » hoc sach, doc sach, thuoc sach
van pham » san pham, van phan, van phat
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
ly nang » ky nang, ly hang, ly vang
va pham » va phat, va phap, va phan
hanh di » hanh vi, hanh de, hang di
di cua » dai cua, doi cua, de cua
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: ((te sach) or (toc sach)) ly nang cau hoi. lieu ((va pham) OR (van pham)) thuc dan hanh di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ly nang cau hoi. lieu ((va pham) OR (van pham)) thuc dan hanh di cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) ly nang cau hoi. lieu ((va pham) OR (van pham)) thuc dan hanh di cua te".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ly nang cau hoi. lieu ((va pham) OR (van pham)) thuc dan hanh di cua te*.