Perhaps you should try some spelling variations:
hoc nganh » hoc nhanh
va thanh » gia thanh, ban thanh, va tinh
va hanh » van hanh, va danh, ban hanh
cac dac » cac dan, cac dai, cac bac
hieu va » lieu va, hieu qua
van hoi » van hoa, van hoc, van hoe
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc nganh ((ky lang) or (ky dang)) van hoi. hieu va cac dac ((va hanh) OR (va thanh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc nganh ((ky lang) OR (ky dang)) van hoi. hieu va cac dac ((va hanh) OR (va thanh)) dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc nganh ((ky lang) or (ky dang)) van hoi. hieu va cac dac ((va hanh) OR (va thanh)) dai cua tre".
• Adding a wildcard symbol may retrieve word variants: hoc nganh ((ky lang) or (ky dang)) van hoi. hieu va cac dac ((va hanh) OR (va thanh)) dai cua tre*.