Perhaps you should try some spelling variations:
tri nang » thi nang, tra nang, tri bang
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
te sach » toc sach
tu nang » tru nang, tu nong, tu nano
va tinh » may tinh
va cua » va chua, via cua, ma cua
ca cua » co cua
x hoi » xa hoi, o hoi, x ho

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 ((tu nang) or (tri nang)) x hoi. hieu van pham duc va tinh ((va cua) or (ca cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((tu nang) OR (tri nang)) x hoi. hieu van pham duc va tinh ((va cua) OR (ca cua)) te.
• Adding a wildcard symbol may retrieve word variants: te sach ((tu nang) or (tri nang)) x hoi. hieu van pham duc va tinh ((va cua) or (ca cua)) te*.