Perhaps you should try some spelling variations:
kmay nang » ky nang, kha nang, may nong
hieu van » hieu va, thien van, lieu va
may nang » may nong, ky nang, cam nang
hanh vai » hanh vi, hanh va, hanh tai
van chat » cao chat
vai cuu » vai cua
tu sach » thu sach, su sach, te sach
cuu tre » cua tre, cau tren, cau treo
luc va » tuc va, loc va

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 ((may nang) or (kmay nang)) xa hoi. hieu van chat ((luc va) OR (duc va)) hanh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((may nang) OR (kmay nang)) xa hoi. hieu van chat ((luc va) OR (duc va)) hanh vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((may nang) or (kmay nang)) xa hoi. hieu van chat ((luc va) OR (duc va)) hanh vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((may nang) or (kmay nang)) xa hoi. hieu van chat ((luc va) OR (duc va)) hanh vai cuu tre*.